Merge branch 'master' of https://github.com/eugenp/tutorials
This commit is contained in:
Ahmed Tawila
116
core-java/src/test/java/com/baeldung/array/SearchArrayTest.java
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116
core-java/src/test/java/com/baeldung/array/SearchArrayTest.java
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@@ -0,0 +1,116 @@
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package com.baeldung.array;
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import org.junit.Test;
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import java.util.*;
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public class SearchArrayTest {
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@Test
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public void searchArrayAllocNewCollections() {
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int count = 1000;
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String[] strings = seedArray(count);
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long startTime = System.nanoTime();
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for (int i = 0; i < count; i++) {
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searchList(strings, "W");
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}
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long duration = System.nanoTime() - startTime;
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System.out.println("SearchList: " + duration / 10000);
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startTime = System.nanoTime();
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for (int i = 0; i < count; i++) {
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searchSet(strings,"S");
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}
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duration = System.nanoTime() - startTime;
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System.out.println("SearchSet: " + duration / 10000);
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startTime = System.nanoTime();
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for (int i = 0; i < count; i++) {
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searchLoop(strings, "T");
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}
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duration = System.nanoTime() - startTime;
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System.out.println("SearchLoop: " + duration / 10000);
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}
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@Test
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public void searchArrayReuseCollections() {
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int count = 10000;
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String[] strings = seedArray(count);
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List<String> asList = Arrays.asList(strings);
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Set<String> asSet = new HashSet<>(Arrays.asList(strings));
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long startTime = System.nanoTime();
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for (int i = 0; i < count; i++) {
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asList.contains("W");
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}
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long duration = System.nanoTime() - startTime;
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System.out.println("List: " + duration / 10000);
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startTime = System.nanoTime();
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for (int i = 0; i < count; i++) {
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asSet.contains("S");
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}
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duration = System.nanoTime() - startTime;
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System.out.println("Set: " + duration / 10000);
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startTime = System.nanoTime();
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for (int i = 0; i < count; i++) {
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searchLoop(strings, "T");
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}
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duration = System.nanoTime() - startTime;
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System.out.println("Loop: " + duration / 10000);
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}
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@Test
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public void searchArrayBinarySearch() {
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int count = 10000;
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String[] strings = seedArray(count);
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Arrays.sort(strings);
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long startTime = System.nanoTime();
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for (int i = 0; i < count; i++) {
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Arrays.binarySearch(strings, "A");
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}
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long duration = System.nanoTime() - startTime;
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System.out.println("Binary search: " + duration / 10000);
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}
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private boolean searchList(String[] strings, String searchString) {
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return Arrays.asList(strings).contains(searchString);
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}
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private boolean searchSet(String[] strings, String searchString) {
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Set<String> set = new HashSet<>(Arrays.asList(strings));
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return set.contains(searchString);
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}
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private boolean searchLoop(String[] strings, String searchString) {
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for (String s : strings) {
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if (s.equals(searchString))
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return true;
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}
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return false;
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}
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private String[] seedArray(int length) {
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String[] strings = new String[length];
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Random random = new Random();
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for (int i = 0; i < length; i++)
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{
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strings[i] = String.valueOf(random.nextInt());
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}
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return strings;
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}
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}
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@@ -0,0 +1,93 @@
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package com.baeldung.collection;
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import java.util.ConcurrentModificationException;
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import java.util.HashSet;
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import java.util.Iterator;
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import java.util.Set;
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import org.junit.Assert;
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import org.junit.Test;
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public class WhenUsingHashSet {
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@Test
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public void whenAddingElement_shouldAddElement() {
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Set<String> hashset = new HashSet<>();
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Assert.assertTrue(hashset.add("String Added"));
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}
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@Test
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public void whenCheckingForElement_shouldSearchForElement() {
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Set<String> hashsetContains = new HashSet<>();
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hashsetContains.add("String Added");
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Assert.assertTrue(hashsetContains.contains("String Added"));
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}
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@Test
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public void whenCheckingTheSizeOfHashSet_shouldReturnThesize() {
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Set<String> hashSetSize = new HashSet<>();
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hashSetSize.add("String Added");
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Assert.assertEquals(1, hashSetSize.size());
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}
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@Test
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public void whenCheckingForEmptyHashSet_shouldCheckForEmpty() {
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Set<String> emptyHashSet = new HashSet<>();
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Assert.assertTrue(emptyHashSet.isEmpty());
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}
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@Test
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public void whenRemovingElement_shouldRemoveElement() {
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Set<String> removeFromHashSet = new HashSet<>();
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removeFromHashSet.add("String Added");
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Assert.assertTrue(removeFromHashSet.remove("String Added"));
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}
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@Test
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public void whenClearingHashSet_shouldClearHashSet() {
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Set<String> clearHashSet = new HashSet<>();
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clearHashSet.add("String Added");
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clearHashSet.clear();
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Assert.assertTrue(clearHashSet.isEmpty());
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}
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@Test
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public void whenIteratingHashSet_shouldIterateHashSet() {
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Set<String> hashset = new HashSet<>();
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hashset.add("First");
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hashset.add("Second");
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hashset.add("Third");
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Iterator<String> itr = hashset.iterator();
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while (itr.hasNext()) {
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System.out.println(itr.next());
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}
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}
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@Test(expected = ConcurrentModificationException.class)
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public void whenModifyingHashSetWhileIterating_shouldThrowException() {
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Set<String> hashset = new HashSet<>();
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hashset.add("First");
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hashset.add("Second");
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hashset.add("Third");
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Iterator<String> itr = hashset.iterator();
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while (itr.hasNext()) {
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itr.next();
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hashset.remove("Second");
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}
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}
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@Test
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public void whenRemovingElementUsingIterator_shouldRemoveElement() {
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Set<String> hashset = new HashSet<>();
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hashset.add("First");
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hashset.add("Second");
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hashset.add("Third");
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Iterator<String> itr = hashset.iterator();
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while (itr.hasNext()) {
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String element = itr.next();
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if (element.equals("Second"))
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itr.remove();
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}
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Assert.assertEquals(2, hashset.size());
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}
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}
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@@ -0,0 +1,157 @@
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package com.baeldung.jdbcrowset;
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import java.io.FileOutputStream;
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import java.io.IOException;
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import java.sql.Connection;
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import java.sql.ResultSet;
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import java.sql.ResultSetMetaData;
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import java.sql.SQLException;
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import java.sql.Statement;
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import javax.sql.rowset.CachedRowSet;
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import javax.sql.rowset.FilteredRowSet;
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import javax.sql.rowset.JdbcRowSet;
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import javax.sql.rowset.JoinRowSet;
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import javax.sql.rowset.RowSetFactory;
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import javax.sql.rowset.RowSetProvider;
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import javax.sql.rowset.WebRowSet;
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import org.junit.Before;
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import org.junit.Test;
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import com.sun.rowset.CachedRowSetImpl;
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import com.sun.rowset.JdbcRowSetImpl;
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import com.sun.rowset.JoinRowSetImpl;
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import com.sun.rowset.WebRowSetImpl;
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public class JdbcRowSetTest {
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Statement stmt = null;
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String username = "sa";
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String password = "";
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String url = "jdbc:h2:mem:testdb";
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String sql = "SELECT * FROM customers";
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@Before
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public void setup() throws Exception {
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Connection conn = DatabaseConfiguration.geth2Connection();
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String drop = "DROP TABLE IF EXISTS customers, associates;";
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String schema = "CREATE TABLE customers (id INT NOT NULL, name VARCHAR(50) NOT NULL, PRIMARY KEY (id)); ";
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String schemapartb = "CREATE TABLE associates (id INT NOT NULL, name VARCHAR(50) NOT NULL, PRIMARY KEY (id));";
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stmt = conn.createStatement();
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stmt.executeUpdate(drop);
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stmt.executeUpdate(schema);
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stmt.executeUpdate(schemapartb);
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DatabaseConfiguration.initDatabase(stmt);
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}
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// JdbcRowSet Example
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@Test
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public void createJdbcRowSet_SelectCustomers_ThenCorrect() throws Exception {
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String sql = "SELECT * FROM customers";
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JdbcRowSet jdbcRS;
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Connection conn = DatabaseConfiguration.geth2Connection();
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jdbcRS = new JdbcRowSetImpl(conn);
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jdbcRS.setType(ResultSet.TYPE_SCROLL_INSENSITIVE);
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jdbcRS.setCommand(sql);
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jdbcRS.execute();
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jdbcRS.addRowSetListener(new ExampleListener());
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while (jdbcRS.next()) {
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// each call to next, generates a cursorMoved event
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System.out.println("id=" + jdbcRS.getString(1));
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System.out.println("name=" + jdbcRS.getString(2));
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}
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}
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// CachedRowSet Example
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@Test
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public void createCachedRowSet_DeleteRecord_ThenCorrect() throws Exception {
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CachedRowSet crs = new CachedRowSetImpl();
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crs.setUsername(username);
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crs.setPassword(password);
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crs.setUrl(url);
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crs.setCommand(sql);
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crs.execute();
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crs.addRowSetListener(new ExampleListener());
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while (crs.next()) {
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if (crs.getInt("id") == 1) {
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System.out.println("CRS found customer1 and will remove the record.");
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crs.deleteRow();
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break;
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}
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}
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}
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// WebRowSet example
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@Test
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public void createWebRowSet_SelectCustomers_WritetoXML_ThenCorrect() throws SQLException, IOException {
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WebRowSet wrs = new WebRowSetImpl();
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wrs.setUsername(username);
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wrs.setPassword(password);
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wrs.setUrl(url);
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wrs.setCommand(sql);
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wrs.execute();
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FileOutputStream ostream = new FileOutputStream("customers.xml");
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wrs.writeXml(ostream);
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}
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// JoinRowSet example
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@Test
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public void createCachedRowSets_DoJoinRowSet_ThenCorrect() throws Exception {
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CachedRowSetImpl customers = new CachedRowSetImpl();
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customers.setUsername(username);
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customers.setPassword(password);
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customers.setUrl(url);
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customers.setCommand(sql);
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customers.execute();
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CachedRowSetImpl associates = new CachedRowSetImpl();
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associates.setUsername(username);
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associates.setPassword(password);
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associates.setUrl(url);
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String associatesSQL = "SELECT * FROM associates";
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associates.setCommand(associatesSQL);
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associates.execute();
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JoinRowSet jrs = new JoinRowSetImpl();
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final String ID = "id";
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final String NAME = "name";
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jrs.addRowSet(customers, ID);
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jrs.addRowSet(associates, ID);
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jrs.last();
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System.out.println("Total rows: " + jrs.getRow());
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jrs.beforeFirst();
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while (jrs.next()) {
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String string1 = jrs.getString(ID);
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String string2 = jrs.getString(NAME);
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System.out.println("ID: " + string1 + ", NAME: " + string2);
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}
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}
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// FilteredRowSet example
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@Test
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public void createFilteredRowSet_filterByRegexExpression_thenCorrect() throws Exception {
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RowSetFactory rsf = RowSetProvider.newFactory();
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FilteredRowSet frs = rsf.createFilteredRowSet();
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frs.setCommand("select * from customers");
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Connection conn = DatabaseConfiguration.geth2Connection();
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frs.execute(conn);
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frs.setFilter(new FilterExample("^[A-C].*"));
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ResultSetMetaData rsmd = frs.getMetaData();
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int columncount = rsmd.getColumnCount();
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while (frs.next()) {
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for (int i = 1; i <= columncount; i++) {
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System.out.println(rsmd.getColumnLabel(i) + " = " + frs.getObject(i) + " ");
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}
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}
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}
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}
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@@ -1,11 +1,38 @@
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package com.baeldung.loops;
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import java.util.ArrayList;
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import java.util.HashMap;
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import java.util.HashSet;
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import java.util.List;
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import java.util.Map;
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import java.util.Map.Entry;
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import java.util.Set;
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import org.junit.Assert;
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import org.junit.BeforeClass;
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import org.junit.Test;
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public class WhenUsingLoops {
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private LoopsInJava loops = new LoopsInJava();
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private static List<String> list = new ArrayList<>();
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private static Set<String> set = new HashSet<>();
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private static Map<String, Integer> map = new HashMap<>();
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@BeforeClass
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public static void setUp() {
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list.add("One");
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list.add("Two");
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list.add("Three");
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set.add("Four");
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set.add("Five");
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set.add("Six");
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map.put("One", 1);
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map.put("Two", 2);
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map.put("Three", 3);
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}
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@Test
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public void shouldRunForLoop() {
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@@ -34,4 +61,47 @@ public class WhenUsingLoops {
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int[] actual = loops.do_while_loop();
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Assert.assertArrayEquals(expected, actual);
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}
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@Test
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public void whenUsingSimpleFor_shouldIterateList() {
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for (int i = 0; i < list.size(); i++) {
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System.out.println(list.get(i));
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}
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}
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@Test
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public void whenUsingEnhancedFor_shouldIterateList() {
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for (String item : list) {
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System.out.println(item);
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}
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}
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@Test
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public void whenUsingEnhancedFor_shouldIterateSet() {
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for (String item : set) {
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System.out.println(item);
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}
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}
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@Test
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public void whenUsingEnhancedFor_shouldIterateMap() {
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for (Entry<String, Integer> entry : map.entrySet()) {
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System.out.println("Key: " + entry.getKey() + " - " + "Value: " + entry.getValue());
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}
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}
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@Test
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public void whenUsingSimpleFor_shouldRunLabelledLoop() {
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aa: for (int i = 1; i <= 3; i++) {
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if (i == 1)
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continue;
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bb: for (int j = 1; j <= 3; j++) {
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if (i == 2 && j == 2) {
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break aa;
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}
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System.out.println(i + " " + j);
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}
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}
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}
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||||
}
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||||
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||||
Reference in New Issue
Block a user