JAVA-22516 Split or move core-java-io-apis-2 module (moved-1) (#14361)
* JAVA-22516 Split or move core-java-io-apis-2 module (moved-1) * JAVA-22516 Adding back the file after fixing the conflicts --------- Co-authored-by: timis1 <noreplay@yahoo.com>
This commit is contained in:
timis1
GitHub
@@ -0,0 +1,29 @@
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package com.baeldung.scanner;
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import java.text.DateFormat;
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import java.text.ParseException;
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import java.text.SimpleDateFormat;
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import java.time.LocalDate;
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import java.time.format.DateTimeFormatter;
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import java.util.Date;
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import java.util.Scanner;
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public class DateScanner {
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LocalDate scanToLocalDate(String input) {
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try (Scanner scanner = new Scanner(input)) {
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String dateString = scanner.next();
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DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy-MM-dd");
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return LocalDate.parse(dateString, formatter);
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}
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}
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Date scanToDate(String input) throws ParseException {
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try (Scanner scanner = new Scanner(input)) {
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String dateString = scanner.next();
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DateFormat formatter = new SimpleDateFormat("yyyy-MM-dd");
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return formatter.parse(dateString);
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}
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}
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}
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@@ -0,0 +1,96 @@
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package com.baeldung.scanner;
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import lombok.extern.log4j.Log4j;
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import org.apache.log4j.LogManager;
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import org.apache.log4j.PropertyConfigurator;
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import java.io.IOException;
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import java.io.InputStream;
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import java.util.Properties;
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import java.util.Scanner;
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@Log4j
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public class HasNextVsHasNextLineDemo {
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private static final String LINE = "----------------------------";
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private static final String END_LINE = "--------OUTPUT--END---------\n";
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private static final String INPUT = new StringBuilder()
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.append("magic\tproject\n")
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.append(" database: oracle\n")
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.append("dependencies:\n")
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.append("spring:foo:bar\n")
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.append("\n").toString();
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private static void hasNextBasic() {
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printHeader("hasNext() Basic");
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Scanner scanner = new Scanner(INPUT);
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while (scanner.hasNext()) {
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log.info(scanner.next());
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}
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log.info(END_LINE);
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scanner.close();
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}
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private static void hasNextWithDelimiter() {
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printHeader("hasNext() with delimiter");
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Scanner scanner = new Scanner(INPUT);
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while (scanner.hasNext()) {
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String token = scanner.next();
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if ("dependencies:".equals(token)) {
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scanner.useDelimiter(":");
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}
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log.info(token);
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}
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log.info(END_LINE);
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scanner.close();
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}
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private static void hasNextWithDelimiterFixed() {
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printHeader("hasNext() with delimiter FIX");
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Scanner scanner = new Scanner(INPUT);
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while (scanner.hasNext()) {
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String token = scanner.next();
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if ("dependencies:".equals(token)) {
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scanner.useDelimiter(":|\\s+");
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}
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log.info(token);
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}
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log.info(END_LINE);
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scanner.close();
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}
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private static void addLineNumber() {
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printHeader("add line number by hasNextLine() ");
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Scanner scanner = new Scanner(INPUT);
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int i = 0;
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while (scanner.hasNextLine()) {
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log.info(String.format("%d|%s", ++i, scanner.nextLine()));
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}
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log.info(END_LINE);
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scanner.close();
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}
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private static void printHeader(String title) {
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log.info(LINE);
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log.info(title);
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log.info(LINE);
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}
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public static void main(String[] args) throws IOException {
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setLogger();
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hasNextBasic();
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hasNextWithDelimiter();
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hasNextWithDelimiterFixed();
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addLineNumber();
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}
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//overwrite the logger config
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private static void setLogger() throws IOException {
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InputStream is = HasNextVsHasNextLineDemo.class.getResourceAsStream("/scanner/log4j.properties");
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Properties props = new Properties();
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props.load(is);
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LogManager.resetConfiguration();
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PropertyConfigurator.configure(props);
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}
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}
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@@ -0,0 +1,56 @@
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package com.baeldung.scanner;
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import java.util.Scanner;
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public class NextLineAfterNextMethods {
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private static void produceSkippingNextLineMethod() {
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try (Scanner scanner = new Scanner(System.in)) {
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System.out.print("Enter your age: ");
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int age = scanner.nextInt();
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System.out.print("Enter your first name: ");
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String firstName = scanner.nextLine(); // Skipped because it reads the remaining newline character
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System.out.println(age + ":" + firstName);
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}
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}
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private static void fixSkippingNextLineMethodV1() {
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try (Scanner scanner = new Scanner(System.in)) {
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System.out.print("Enter your age: ");
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int age = scanner.nextInt();
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scanner.nextLine();
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System.out.print("Enter your first name: ");
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String firstName = scanner.nextLine();
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System.out.println(age + ":" + firstName);
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}
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}
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private static void fixSkippingNextLineMethodV2() {
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try (Scanner scanner = new Scanner(System.in)) {
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System.out.print("Enter your age: ");
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int age = Integer.parseInt(scanner.nextLine());
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System.out.print("Enter your first name: ");
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String firstName = scanner.nextLine();
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System.out.println(age + ":" + firstName);
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}
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}
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private static void fixSkippingNextLineMethodV3() {
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try (Scanner scanner = new Scanner(System.in)) {
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System.out.print("Enter your age: ");
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int age = scanner.nextInt();
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scanner.skip("\r\n");
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System.out.print("Enter your first name: ");
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String firstName = scanner.nextLine();
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System.out.println(age + ":" + firstName);
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}
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}
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public static void main(String[] args) {
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produceSkippingNextLineMethod();
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fixSkippingNextLineMethodV1();
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fixSkippingNextLineMethodV2();
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fixSkippingNextLineMethodV3();
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}
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}
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@@ -0,0 +1,58 @@
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package com.baeldung.scanner;
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import java.io.IOException;
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import java.nio.file.Files;
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import java.nio.file.Path;
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import java.nio.file.Paths;
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import java.util.NoSuchElementException;
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import java.util.Scanner;
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public class ScannerNoSuchElementException {
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public static String readFileV1(String pathname) throws IOException {
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Path pathFile = Paths.get(pathname);
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if (Files.notExists(pathFile)) {
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return "";
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}
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try (Scanner scanner = new Scanner(pathFile)) {
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return scanner.nextLine();
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}
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}
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public static String readFileV2(String pathname) throws IOException {
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Path pathFile = Paths.get(pathname);
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if (Files.notExists(pathFile)) {
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return "";
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}
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try (Scanner scanner = new Scanner(pathFile)) {
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return scanner.hasNextLine() ? scanner.nextLine() : "";
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}
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}
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public static String readFileV3(String pathname) throws IOException {
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Path pathFile = Paths.get(pathname);
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if (Files.notExists(pathFile) || Files.size(pathFile) == 0) {
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return "";
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}
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try (Scanner scanner = new Scanner(pathFile)) {
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return scanner.nextLine();
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}
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}
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public static String readFileV4(String pathname) throws IOException {
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Path pathFile = Paths.get(pathname);
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if (Files.notExists(pathFile)) {
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return "";
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}
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try (Scanner scanner = new Scanner(pathFile)) {
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return scanner.nextLine();
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} catch (NoSuchElementException exception) {
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return "";
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}
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}
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}
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@@ -0,0 +1,71 @@
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package com.baeldung.emptyfile;
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import static org.junit.jupiter.api.Assertions.assertEquals;
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import static org.junit.jupiter.api.Assertions.assertFalse;
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import static org.junit.jupiter.api.Assertions.assertThrows;
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import static org.junit.jupiter.api.Assertions.assertTrue;
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import java.io.File;
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import java.io.IOException;
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import java.nio.file.Files;
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import java.nio.file.NoSuchFileException;
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import java.nio.file.Path;
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import org.junit.jupiter.api.Test;
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import org.junit.jupiter.api.io.TempDir;
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public class CheckFileIsEmptyUnitTest {
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@Test
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void whenTheFileIsEmpty_thenFileLengthIsZero(@TempDir Path tempDir) throws IOException {
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File emptyFile = tempDir.resolve("an-empty-file.txt")
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.toFile();
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emptyFile.createNewFile();
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assertTrue(emptyFile.exists());
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assertEquals(0, emptyFile.length());
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}
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@Test
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void whenFileDoesNotExist_thenFileLengthIsZero(@TempDir Path tempDir) {
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File aNewFile = tempDir.resolve("a-new-file.txt")
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.toFile();
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assertFalse(aNewFile.exists());
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assertEquals(0, aNewFile.length());
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}
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boolean isFileEmpty(File file) {
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if (!file.exists()) {
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throw new IllegalArgumentException("Cannot check the file length. The file is not found: " + file.getAbsolutePath());
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}
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return file.length() == 0;
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}
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@Test
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void whenTheFileDoesNotExist_thenIsFilesEmptyThrowsException(@TempDir Path tempDir) {
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File aNewFile = tempDir.resolve("a-new-file.txt")
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.toFile();
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IllegalArgumentException ex = assertThrows(IllegalArgumentException.class, () -> isFileEmpty(aNewFile));
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assertEquals(ex.getMessage(), "Cannot check the file length. The file is not found: " + aNewFile.getAbsolutePath());
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}
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@Test
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void whenTheFileIsEmpty_thenIsFilesEmptyReturnsTrue(@TempDir Path tempDir) throws IOException {
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File emptyFile = tempDir.resolve("an-empty-file.txt")
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.toFile();
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emptyFile.createNewFile();
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assertTrue(isFileEmpty(emptyFile));
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}
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@Test
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void whenTheFileIsEmpty_thenFilesSizeReturnsTrue(@TempDir Path tempDir) throws IOException {
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Path emptyFilePath = tempDir.resolve("an-empty-file.txt");
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Files.createFile(emptyFilePath);
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assertEquals(0, Files.size(emptyFilePath));
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}
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@Test
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void whenTheFileDoesNotExist_thenFilesSizeThrowsException(@TempDir Path tempDir) {
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Path aNewFilePath = tempDir.resolve("a-new-file.txt");
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assertThrows(NoSuchFileException.class, () -> Files.size(aNewFilePath));
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}
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}
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@@ -0,0 +1,26 @@
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package com.baeldung.scanner;
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import static org.junit.jupiter.api.Assertions.assertEquals;
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import java.text.ParseException;
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import java.text.SimpleDateFormat;
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import java.time.LocalDate;
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import java.time.format.DateTimeFormatter;
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import org.junit.jupiter.api.Test;
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class DateScannerUnitTest {
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@Test
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void whenScanToLocalDate_ThenCorrectLocalDate() {
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String dateString = "2018-09-09";
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assertEquals(LocalDate.parse(dateString, DateTimeFormatter.ofPattern("yyyy-MM-dd")), new DateScanner().scanToLocalDate(dateString));
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}
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@Test
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void whenScanToDate_ThenCorrectDate() throws ParseException {
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String dateString = "2018-09-09";
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assertEquals(new SimpleDateFormat("yyyy-MM-dd").parse(dateString), new DateScanner().scanToDate(dateString));
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}
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}
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@@ -0,0 +1,97 @@
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package com.baeldung.scanner;
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import static org.junit.jupiter.api.Assertions.assertArrayEquals;
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import static org.junit.jupiter.api.Assertions.assertEquals;
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import java.util.ArrayList;
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import java.util.List;
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import java.util.Scanner;
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import org.junit.jupiter.api.Test;
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import com.google.common.collect.Lists;
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public class InputWithSpacesUnitTest {
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@Test
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void whenValuesContainSpaces_thenNextBreaksTheValue() {
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String input = new StringBuilder().append("Michael Jackson\n")
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.append("He was the 'King of Pop'.\n")
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.toString();
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Scanner sc = new Scanner(input);
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String name = sc.next();
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String description = sc.next();
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assertEquals("Michael", name);
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assertEquals("Jackson", description);
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}
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@Test
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void whenOneValuePerLineUsingNextLine_thenGetExpectedResult() {
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String input = new StringBuilder().append("Michael Jackson\n")
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.append("He was the 'King of Pop'.\n")
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.toString();
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Scanner sc = new Scanner(input);
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String name = sc.nextLine();
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String description = sc.nextLine();
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assertEquals("Michael Jackson", name);
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assertEquals("He was the 'King of Pop'.", description);
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}
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@Test
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void whenOneValuePerLineUsingNewLineAsDelimiter_thenGetExpectedResult() {
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String input = new StringBuilder().append("Michael Jackson\n")
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.append("He was the 'King of Pop'.\n")
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.toString();
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Scanner sc = new Scanner(input);
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sc.useDelimiter("\\n");
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String name = sc.next();
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String description = sc.next();
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assertEquals("Michael Jackson", name);
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assertEquals("He was the 'King of Pop'.", description);
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}
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@Test
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void whenValuesAreSeparatedByCommaUsingSplit_thenGetExpectedResult() {
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String input = "Michael Jackson, Whitney Houston, John Lennon\n";
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Scanner sc = new Scanner(input);
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String[] names = sc.nextLine()
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.split(", ");
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assertArrayEquals(new String[] { "Michael Jackson", "Whitney Houston", "John Lennon" }, names);
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}
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@Test
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void whenValuesAreSeparatedByCommaSettingDelimiterWithoutNewline_thenGetExpectedResult() {
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String input = new StringBuilder().append("Michael Jackson, Whitney Houston, John Lennon\n")
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.append("Elvis Presley\n")
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.toString();
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Scanner sc = new Scanner(input);
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sc.useDelimiter(", ");
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List<String> names = new ArrayList<>();
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while (sc.hasNext()) {
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names.add(sc.next());
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}
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//assertEquals(Lists.newArrayList("Michael Jackson", "Whitney Houston", "John Lennon", "Elvis Presley"), names); <-- Fail
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assertEquals(3, names.size());
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assertEquals("John Lennon\nElvis Presley\n", names.get(2));
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}
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@Test
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void whenValuesAreSeparatedByCommaSettingDelimiter_thenGetExpectedResult() {
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String input = new StringBuilder().append("Michael Jackson, Whitney Houston, John Lennon\n")
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.append("Elvis Presley\n")
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.toString();
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Scanner sc = new Scanner(input);
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sc.useDelimiter(", |\\n");
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List<String> names = new ArrayList<>();
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while (sc.hasNext()) {
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names.add(sc.next());
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}
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assertEquals(Lists.newArrayList("Michael Jackson", "Whitney Houston", "John Lennon", "Elvis Presley"), names);
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}
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}
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@@ -0,0 +1,200 @@
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package com.baeldung.scanner;
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import static org.junit.Assert.assertEquals;
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import static org.junit.Assert.assertNull;
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import static org.junit.Assert.assertTrue;
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import java.io.BufferedReader;
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import java.io.ByteArrayInputStream;
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import java.io.File;
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import java.io.FileInputStream;
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import java.io.FileReader;
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import java.io.IOException;
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import java.io.InputStream;
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import java.util.Locale;
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import java.util.NoSuchElementException;
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import java.util.Scanner;
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import org.junit.Test;
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public class JavaScannerUnitTest {
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@Test
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public void whenReadFileWithScanner_thenCorrect() throws IOException {
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final Scanner scanner = new Scanner(new File("src/test/resources/test_read.in"));
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assertTrue(scanner.hasNext());
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assertEquals("Hello", scanner.next());
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assertEquals("world", scanner.next());
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scanner.close();
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}
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@Test
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public void whenConvertInputStreamToString_thenConverted() throws IOException {
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final String expectedValue = "Hello world";
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final FileInputStream inputStream = new FileInputStream("src/test/resources/test_read.in");
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final Scanner scanner = new Scanner(inputStream);
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scanner.useDelimiter("\\A");
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final String result = scanner.next();
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assertEquals(expectedValue, result);
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scanner.close();
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}
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@Test
|
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public void whenReadUsingBufferedReader_thenCorrect() throws IOException {
|
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final String firstLine = "Hello world";
|
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final String secondLine = "Hi, John";
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final BufferedReader reader = new BufferedReader(new FileReader("src/test/resources/test_read_multiple.in"));
|
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String result = reader.readLine();
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assertEquals(firstLine, result);
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result = reader.readLine();
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assertEquals(secondLine, result);
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reader.close();
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}
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@Test
|
||||
public void whenReadUsingScanner_thenCorrect() throws IOException {
|
||||
final String firstLine = "Hello world";
|
||||
final FileInputStream inputStream = new FileInputStream("src/test/resources/test_read_multiple.in");
|
||||
final Scanner scanner = new Scanner(inputStream);
|
||||
|
||||
final String result = scanner.nextLine();
|
||||
assertEquals(firstLine, result);
|
||||
|
||||
scanner.useDelimiter(", ");
|
||||
assertEquals("Hi", scanner.next());
|
||||
assertEquals("John", scanner.next());
|
||||
|
||||
scanner.close();
|
||||
}
|
||||
|
||||
@Test
|
||||
public void whenReadingInputFromConsole_thenCorrect() {
|
||||
final String input = "Hello";
|
||||
final InputStream stdin = System.in;
|
||||
System.setIn(new ByteArrayInputStream(input.getBytes()));
|
||||
|
||||
final Scanner scanner = new Scanner(System.in);
|
||||
final String result = scanner.next();
|
||||
assertEquals(input, result);
|
||||
|
||||
System.setIn(stdin);
|
||||
scanner.close();
|
||||
}
|
||||
|
||||
@Test
|
||||
public void whenValidateInputUsingScanner_thenValidated() throws IOException {
|
||||
final String input = "2000";
|
||||
final InputStream stdin = System.in;
|
||||
System.setIn(new ByteArrayInputStream(input.getBytes()));
|
||||
|
||||
final Scanner scanner = new Scanner(System.in);
|
||||
|
||||
final boolean isIntInput = scanner.hasNextInt();
|
||||
assertTrue(isIntInput);
|
||||
|
||||
System.setIn(stdin);
|
||||
scanner.close();
|
||||
}
|
||||
|
||||
@Test
|
||||
public void whenScanString_thenCorrect() throws IOException {
|
||||
final String input = "Hello 1 F 3.5";
|
||||
final Scanner scanner = new Scanner(input);
|
||||
scanner.useLocale(Locale.US);
|
||||
|
||||
assertEquals("Hello", scanner.next());
|
||||
assertEquals(1, scanner.nextInt());
|
||||
assertEquals(15, scanner.nextInt(16));
|
||||
assertEquals(3.5, scanner.nextDouble(), 0.00000001);
|
||||
|
||||
scanner.close();
|
||||
}
|
||||
|
||||
@Test
|
||||
public void whenFindPatternUsingScanner_thenFound() throws IOException {
|
||||
final String expectedValue = "world";
|
||||
final FileInputStream inputStream = new FileInputStream("src/test/resources/test_read.in");
|
||||
final Scanner scanner = new Scanner(inputStream);
|
||||
|
||||
final String result = scanner.findInLine("wo..d");
|
||||
assertEquals(expectedValue, result);
|
||||
|
||||
scanner.close();
|
||||
}
|
||||
|
||||
@Test
|
||||
public void whenFindPatternInHorizon_thenFound() throws IOException {
|
||||
final String expectedValue = "world";
|
||||
final FileInputStream inputStream = new FileInputStream("src/test/resources/test_read.in");
|
||||
final Scanner scanner = new Scanner(inputStream);
|
||||
|
||||
String result = scanner.findWithinHorizon("wo..d", 5);
|
||||
assertNull(result);
|
||||
|
||||
result = scanner.findWithinHorizon("wo..d", 100);
|
||||
assertEquals(expectedValue, result);
|
||||
|
||||
scanner.close();
|
||||
}
|
||||
|
||||
@Test
|
||||
public void whenSkipPatternUsingScanner_thenSkiped() throws IOException {
|
||||
final FileInputStream inputStream = new FileInputStream("src/test/resources/test_read.in");
|
||||
final Scanner scanner = new Scanner(inputStream);
|
||||
|
||||
scanner.skip(".e.lo");
|
||||
|
||||
assertEquals("world", scanner.next());
|
||||
|
||||
scanner.close();
|
||||
}
|
||||
|
||||
@Test
|
||||
public void whenChangeScannerDelimiter_thenChanged() throws IOException {
|
||||
final String expectedValue = "Hello world";
|
||||
final String[] splited = expectedValue.split("o");
|
||||
|
||||
final FileInputStream inputStream = new FileInputStream("src/test/resources/test_read.in");
|
||||
final Scanner scanner = new Scanner(inputStream);
|
||||
scanner.useDelimiter("o");
|
||||
|
||||
assertEquals(splited[0], scanner.next());
|
||||
assertEquals(splited[1], scanner.next());
|
||||
assertEquals(splited[2], scanner.next());
|
||||
|
||||
scanner.close();
|
||||
}
|
||||
|
||||
@Test
|
||||
public void whenReadWithScannerTwoDelimiters_thenCorrect() throws IOException {
|
||||
final Scanner scanner = new Scanner(new File("src/test/resources/test_read_d.in"));
|
||||
scanner.useDelimiter(",|-");
|
||||
|
||||
assertEquals("John", scanner.next());
|
||||
assertEquals("Adam", scanner.next());
|
||||
assertEquals("Tom", scanner.next());
|
||||
|
||||
scanner.close();
|
||||
}
|
||||
|
||||
@Test(expected = NoSuchElementException.class)
|
||||
public void givenClosingScanner_whenReading_thenThrowException() throws IOException {
|
||||
final FileInputStream inputStream = new FileInputStream("src/test/resources/test_read.in");
|
||||
|
||||
final Scanner scanner = new Scanner(inputStream);
|
||||
scanner.next();
|
||||
scanner.close();
|
||||
|
||||
final Scanner scanner2 = new Scanner(inputStream);
|
||||
scanner2.next();
|
||||
scanner2.close();
|
||||
}
|
||||
|
||||
}
|
||||
@@ -0,0 +1,85 @@
|
||||
package com.baeldung.scanner;
|
||||
|
||||
import static org.junit.jupiter.api.Assertions.assertEquals;
|
||||
import static org.junit.jupiter.api.Assertions.assertThrows;
|
||||
|
||||
import java.util.InputMismatchException;
|
||||
import java.util.Scanner;
|
||||
|
||||
import org.junit.jupiter.api.Test;
|
||||
|
||||
public class NextLineVsNextIntUnitTest {
|
||||
|
||||
@Test
|
||||
void whenInputLineIsNumber_thenNextLineAndNextIntBothWork() {
|
||||
String input = "42\n";
|
||||
|
||||
//nextLine()
|
||||
Scanner sc1 = new Scanner(input);
|
||||
int num1 = Integer.parseInt(sc1.nextLine());
|
||||
assertEquals(42, num1);
|
||||
|
||||
//nextInt()
|
||||
Scanner sc2 = new Scanner(input);
|
||||
int num2 = sc2.nextInt();
|
||||
assertEquals(42, num2);
|
||||
|
||||
}
|
||||
|
||||
@Test
|
||||
void whenInputIsNotValidNumber_thenNextLineAndNextIntThrowDifferentException() {
|
||||
String input = "Nan\n";
|
||||
|
||||
//nextLine() -> NumberFormatException
|
||||
Scanner sc1 = new Scanner(input);
|
||||
assertThrows(NumberFormatException.class, () -> Integer.parseInt(sc1.nextLine()));
|
||||
|
||||
//nextInt() -> InputMismatchException
|
||||
Scanner sc2 = new Scanner(input);
|
||||
assertThrows(InputMismatchException.class, sc2::nextInt);
|
||||
}
|
||||
|
||||
@Test
|
||||
void whenUsingNextInt_thenTheNextTokenAfterItFailsToParseIsNotConsumed() {
|
||||
String input = "42 is a magic number\n";
|
||||
|
||||
//nextInt() to read '42'
|
||||
Scanner sc2 = new Scanner(input);
|
||||
int num2 = sc2.nextInt();
|
||||
assertEquals(42, num2);
|
||||
|
||||
// call nextInt() again on "is"
|
||||
assertThrows(InputMismatchException.class, sc2::nextInt);
|
||||
|
||||
String theNextToken = sc2.next();
|
||||
assertEquals("is", theNextToken);
|
||||
|
||||
theNextToken = sc2.next();
|
||||
assertEquals("a", theNextToken);
|
||||
}
|
||||
|
||||
@Test
|
||||
void whenReadingTwoInputLines_thenNextLineAndNextIntBehaveDifferently() {
|
||||
|
||||
String input = new StringBuilder().append("42\n")
|
||||
.append("It is a magic number.\n")
|
||||
.toString();
|
||||
|
||||
//nextLine()
|
||||
Scanner sc1 = new Scanner(input);
|
||||
int num1 = Integer.parseInt(sc1.nextLine());
|
||||
String nextLineText1 = sc1.nextLine();
|
||||
assertEquals(42, num1);
|
||||
assertEquals("It is a magic number.", nextLineText1);
|
||||
|
||||
//nextInt()
|
||||
Scanner sc2 = new Scanner(input);
|
||||
int num2 = sc2.nextInt();
|
||||
assertEquals(42, num2);
|
||||
|
||||
// nextInt() leaves the newline character (\n) behind
|
||||
String nextLineText2 = sc2.nextLine();
|
||||
assertEquals("", nextLineText2);
|
||||
}
|
||||
|
||||
}
|
||||
@@ -0,0 +1,51 @@
|
||||
package com.baeldung.scanner;
|
||||
|
||||
import static org.junit.jupiter.api.Assertions.assertEquals;
|
||||
|
||||
import java.util.Scanner;
|
||||
|
||||
import org.junit.jupiter.api.Test;
|
||||
|
||||
class NextVsNextLineUnitTest {
|
||||
|
||||
@Test
|
||||
void givenInput_whenUsingNextMethod_thenReturnToken() {
|
||||
String input = "Hello world";
|
||||
try (Scanner scanner = new Scanner(input)) {
|
||||
assertEquals("Hello", scanner.next());
|
||||
assertEquals("world", scanner.next());
|
||||
}
|
||||
}
|
||||
|
||||
@Test
|
||||
void givenInput_whenUsingNextMethodWithCustomDelimiter_thenReturnToken() {
|
||||
String input = "Hello :world";
|
||||
try (Scanner scanner = new Scanner(input)) {
|
||||
scanner.useDelimiter(":");
|
||||
|
||||
assertEquals("Hello ", scanner.next());
|
||||
assertEquals("world", scanner.next());
|
||||
}
|
||||
}
|
||||
|
||||
@Test
|
||||
void givenInput_whenUsingNextLineMethod_thenReturnEntireLine() {
|
||||
String input = "Hello world\nWelcome to baeldung.com";
|
||||
try (Scanner scanner = new Scanner(input)) {
|
||||
assertEquals("Hello world", scanner.nextLine());
|
||||
assertEquals("Welcome to baeldung.com", scanner.nextLine());
|
||||
}
|
||||
}
|
||||
|
||||
@Test
|
||||
void givenInput_whenUsingNextLineWithCustomDelimiter_thenIgnoreDelimiter() {
|
||||
String input = "Hello:world\nWelcome:to baeldung.com";
|
||||
try (Scanner scanner = new Scanner(input)) {
|
||||
scanner.useDelimiter(":");
|
||||
|
||||
assertEquals("Hello:world", scanner.nextLine());
|
||||
assertEquals("Welcome:to baeldung.com", scanner.nextLine());
|
||||
}
|
||||
}
|
||||
|
||||
}
|
||||
@@ -0,0 +1,38 @@
|
||||
package com.baeldung.scanner;
|
||||
|
||||
import static org.junit.jupiter.api.Assertions.assertEquals;
|
||||
|
||||
import java.util.Scanner;
|
||||
|
||||
import org.junit.jupiter.api.Test;
|
||||
|
||||
public class ScanACharacterUnitTest {
|
||||
|
||||
// given - input scanner source, no need to scan from console
|
||||
String input = new StringBuilder().append("abc\n")
|
||||
.append("mno\n")
|
||||
.append("xyz\n")
|
||||
.toString();
|
||||
|
||||
@Test
|
||||
public void givenInputSource_whenScanCharUsingNext_thenOneCharIsRead() {
|
||||
Scanner sc = new Scanner(input);
|
||||
char c = sc.next().charAt(0);
|
||||
assertEquals('a', c);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void givenInputSource_whenScanCharUsingFindInLine_thenOneCharIsRead() {
|
||||
Scanner sc = new Scanner(input);
|
||||
char c = sc.findInLine(".").charAt(0);
|
||||
assertEquals('a', c);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void givenInputSource_whenScanCharUsingUseDelimiter_thenOneCharIsRead() {
|
||||
Scanner sc = new Scanner(input);
|
||||
char c = sc.useDelimiter("").next().charAt(0);
|
||||
assertEquals('a', c);
|
||||
}
|
||||
|
||||
}
|
||||
@@ -0,0 +1,43 @@
|
||||
package com.baeldung.scanner;
|
||||
|
||||
import static org.junit.jupiter.api.Assertions.assertEquals;
|
||||
import static org.junit.jupiter.api.Assertions.assertThrows;
|
||||
|
||||
import java.io.IOException;
|
||||
import java.util.NoSuchElementException;
|
||||
|
||||
import org.junit.jupiter.api.Test;
|
||||
|
||||
class ScannerNoSuchElementExceptionUnitTest {
|
||||
|
||||
@Test
|
||||
void givenEmptyFile_whenUsingReadFileV1_thenThrowException() {
|
||||
Exception exception = assertThrows(NoSuchElementException.class, () -> {
|
||||
ScannerNoSuchElementException.readFileV1("src/test/resources/emptyFile.txt");
|
||||
});
|
||||
|
||||
assertEquals("No line found", exception.getMessage());
|
||||
}
|
||||
|
||||
@Test
|
||||
void givenEmptyFile_whenUsingReadFileV2_thenSuccess() throws IOException {
|
||||
String emptyLine = ScannerNoSuchElementException.readFileV2("src/test/resources/emptyFile.txt");
|
||||
|
||||
assertEquals("", emptyLine);
|
||||
}
|
||||
|
||||
@Test
|
||||
void givenEmptyFile_whenUsingReadFileV3_thenSuccess() throws IOException {
|
||||
String emptyLine = ScannerNoSuchElementException.readFileV3("src/test/resources/emptyFile.txt");
|
||||
|
||||
assertEquals("", emptyLine);
|
||||
}
|
||||
|
||||
@Test
|
||||
void givenEmptyFile_whenUsingReadFileV4_thenSuccess() throws IOException {
|
||||
String emptyLine = ScannerNoSuchElementException.readFileV4("src/test/resources/emptyFile.txt");
|
||||
|
||||
assertEquals("", emptyLine);
|
||||
}
|
||||
|
||||
}
|
||||
@@ -0,0 +1,107 @@
|
||||
package com.baeldung.scanner;
|
||||
|
||||
import static org.junit.jupiter.api.Assertions.assertArrayEquals;
|
||||
import static org.junit.jupiter.api.Assertions.assertEquals;
|
||||
|
||||
import java.util.ArrayList;
|
||||
import java.util.List;
|
||||
import java.util.Scanner;
|
||||
|
||||
import org.junit.jupiter.api.Test;
|
||||
|
||||
import com.google.common.collect.Lists;
|
||||
import com.google.common.collect.ObjectArrays;
|
||||
|
||||
public class ScannerToArrayUnitTest {
|
||||
|
||||
@Test
|
||||
void whenMultipleElementsInOneLine_thenGetExpectedArray() {
|
||||
String input = "Java Kotlin Ruby Python Go\n";
|
||||
String[] expected = new String[] { "Java", "Kotlin", "Ruby", "Python", "Go" };
|
||||
|
||||
// scanner.next()
|
||||
Scanner scanner1 = new Scanner(input);
|
||||
String[] result1 = new String[5];
|
||||
int i = 0;
|
||||
while (i < result1.length) {
|
||||
result1[i] = scanner1.next();
|
||||
i++;
|
||||
}
|
||||
assertArrayEquals(expected, result1);
|
||||
|
||||
//split()
|
||||
Scanner scanner2 = new Scanner(input);
|
||||
String[] result2 = scanner2.nextLine()
|
||||
.split("\\s+");
|
||||
assertArrayEquals(expected, result2);
|
||||
}
|
||||
|
||||
@Test
|
||||
void whenOneElementPerLine_thenGetExpectedArray() {
|
||||
String input = new StringBuilder().append("Baeldung Java\n")
|
||||
.append("Baeldung Kotlin\n")
|
||||
.append("Baeldung Linux\n")
|
||||
.toString();
|
||||
|
||||
String[] expected = new String[] { "Baeldung Java", "Baeldung Kotlin", "Baeldung Linux" };
|
||||
|
||||
String[] result = new String[3];
|
||||
Scanner scanner = new Scanner(input);
|
||||
int i = 0;
|
||||
while (i < result.length) {
|
||||
result[i] = scanner.nextLine();
|
||||
i++;
|
||||
}
|
||||
assertArrayEquals(expected, result);
|
||||
}
|
||||
|
||||
@Test
|
||||
void whenOneElementPerLine_thenGetExpectedList() {
|
||||
String input = new StringBuilder().append("Baeldung Java\n")
|
||||
.append("Baeldung Kotlin\n")
|
||||
.append("Baeldung Linux\n")
|
||||
.toString();
|
||||
|
||||
List<String> expected = Lists.newArrayList("Baeldung Java", "Baeldung Kotlin", "Baeldung Linux");
|
||||
|
||||
List<String> result = new ArrayList<>();
|
||||
Scanner scanner = new Scanner(input);
|
||||
while (scanner.hasNextLine()) {
|
||||
result.add(scanner.nextLine());
|
||||
}
|
||||
assertEquals(expected, result);
|
||||
}
|
||||
|
||||
@Test
|
||||
void whenEveryTokenIsAnElement_thenGetExpectedList() {
|
||||
String input = new StringBuilder().append("Linux Windows MacOS\n")
|
||||
.append("Java Kotlin Python Go\n")
|
||||
.toString();
|
||||
|
||||
List<String> expected = Lists.newArrayList("Linux", "Windows", "MacOS", "Java", "Kotlin", "Python", "Go");
|
||||
List<String> result = new ArrayList<>();
|
||||
Scanner scanner = new Scanner(input);
|
||||
while (scanner.hasNext()) {
|
||||
result.add(scanner.next());
|
||||
}
|
||||
assertEquals(expected, result);
|
||||
}
|
||||
|
||||
@Test
|
||||
void whenEveryTokenIsAnElement_thenGetExpectedArray() {
|
||||
String input = new StringBuilder().append("Linux Windows MacOS\n")
|
||||
.append("Java Kotlin Python Go\n")
|
||||
.toString();
|
||||
|
||||
String[] expected = new String[] { "Linux", "Windows", "MacOS", "Java", "Kotlin", "Python", "Go" };
|
||||
String[] result = new String[] {};
|
||||
|
||||
Scanner scanner = new Scanner(input);
|
||||
while (scanner.hasNextLine()) {
|
||||
String[] lineInArray = scanner.nextLine()
|
||||
.split("\\s+");
|
||||
result = ObjectArrays.concat(result, lineInArray, String.class);
|
||||
}
|
||||
assertArrayEquals(expected, result);
|
||||
}
|
||||
}
|
||||
@@ -0,0 +1,44 @@
|
||||
package com.baeldung.scannernextline;
|
||||
|
||||
import static org.junit.Assert.assertEquals;
|
||||
|
||||
import java.util.NoSuchElementException;
|
||||
import java.util.Scanner;
|
||||
|
||||
import org.junit.Test;
|
||||
|
||||
public class ScannerNextLineUnitTest {
|
||||
|
||||
@Test
|
||||
public void whenReadingLines_thenCorrect() {
|
||||
String input = "Scanner\nTest\n";
|
||||
try (Scanner scanner = new Scanner(input)) {
|
||||
assertEquals("Scanner", scanner.nextLine());
|
||||
assertEquals("Test", scanner.nextLine());
|
||||
}
|
||||
}
|
||||
|
||||
@Test
|
||||
public void whenReadingPartialLines_thenCorrect() {
|
||||
String input = "Scanner\n";
|
||||
try (Scanner scanner = new Scanner(input)) {
|
||||
scanner.useDelimiter("");
|
||||
scanner.next();
|
||||
assertEquals("canner", scanner.nextLine());
|
||||
}
|
||||
}
|
||||
|
||||
@Test(expected = NoSuchElementException.class)
|
||||
public void givenNoNewLine_whenReadingNextLine_thenThrowNoSuchElementException() {
|
||||
try (Scanner scanner = new Scanner("")) {
|
||||
String result = scanner.nextLine();
|
||||
}
|
||||
}
|
||||
|
||||
@Test(expected = IllegalStateException.class)
|
||||
public void givenScannerIsClosed_whenReadingNextLine_thenThrowIllegalStateException() {
|
||||
Scanner scanner = new Scanner("");
|
||||
scanner.close();
|
||||
String result = scanner.nextLine();
|
||||
}
|
||||
}
|
||||
@@ -0,0 +1 @@
|
||||
Hello world
|
||||
@@ -0,0 +1 @@
|
||||
John,Adam-Tom
|
||||
@@ -0,0 +1,2 @@
|
||||
Hello world
|
||||
Hi, John
|
||||
Reference in New Issue
Block a user