BAEL-6403 - Extracting a Tar File in Java (#14240)

* code 1

* sibling module readme

* new module

* review 1

* review 2

libraries-apache-commons-2/src/main/java/com/baeldung/commons/untar/Resources.java

@@ -0,0 +1,14 @@
+package com.baeldung.commons.untar;
+
+import java.io.InputStream;
+
+public interface Resources {
+
+    static InputStream tarFile() {
+        return Resources.class.getResourceAsStream("/untar/test.tar");
+    }
+
+    static InputStream tarGzFile() {
+        return Resources.class.getResourceAsStream("/untar/test.tar.gz");
+    }
+}

libraries-apache-commons-2/src/main/java/com/baeldung/commons/untar/TarExtractor.java

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+package com.baeldung.commons.untar;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.file.Files;
+import java.nio.file.Path;
+
+public abstract class TarExtractor {
+
+    private InputStream tarStream;
+    private boolean gzip;
+    private Path destination;
+
+    protected TarExtractor(InputStream in, boolean gzip, Path destination) throws IOException {
+        this.tarStream = in;
+        this.gzip = gzip;
+        this.destination = destination;
+
+        Files.createDirectories(destination);
+    }
+
+    protected TarExtractor(Path tarFile, Path destination) throws IOException {
+        this(Files.newInputStream(tarFile), tarFile.endsWith("gz"), destination);
+    }
+
+    public Path getDestination() {
+        return destination;
+    }
+
+    public InputStream getTarStream() {
+        return tarStream;
+    }
+
+    public boolean isGzip() {
+        return gzip;
+    }
+
+    public abstract void untar() throws IOException;
+}

libraries-apache-commons-2/src/main/java/com/baeldung/commons/untar/impl/TarExtractorAnt.java

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+package com.baeldung.commons.untar.impl;
+
+import java.io.BufferedInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.StandardCopyOption;
+import java.util.zip.GZIPInputStream;
+
+import org.apache.tools.tar.TarEntry;
+import org.apache.tools.tar.TarInputStream;
+
+import com.baeldung.commons.untar.TarExtractor;
+
+public class TarExtractorAnt extends TarExtractor {
+
+    public TarExtractorAnt(InputStream in, boolean gzip, Path destination) throws IOException {
+        super(in, gzip, destination);
+    }
+
+    @Override
+    public void untar() throws IOException {
+        try (TarInputStream tar = new TarInputStream(new BufferedInputStream( //
+                isGzip() ? new GZIPInputStream(getTarStream()) : getTarStream()))) {
+            TarEntry entry;
+            while ((entry = tar.getNextEntry()) != null) {
+                Path extractTo = getDestination().resolve(entry.getName());
+                if (entry.isDirectory()) {
+                    Files.createDirectories(extractTo);
+                } else {
+                    Files.copy(tar, extractTo, StandardCopyOption.REPLACE_EXISTING);
+                }
+            }
+        }
+    }
+}

libraries-apache-commons-2/src/main/java/com/baeldung/commons/untar/impl/TarExtractorCommonsCompress.java

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+package com.baeldung.commons.untar.impl;
+
+import java.io.BufferedInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.StandardCopyOption;
+
+import org.apache.commons.compress.archivers.ArchiveEntry;
+import org.apache.commons.compress.archivers.tar.TarArchiveInputStream;
+import org.apache.commons.compress.compressors.gzip.GzipCompressorInputStream;
+
+import com.baeldung.commons.untar.TarExtractor;
+
+public class TarExtractorCommonsCompress extends TarExtractor {
+
+    public TarExtractorCommonsCompress(InputStream in, boolean gzip, Path destination) throws IOException {
+        super(in, gzip, destination);
+    }
+
+    @Override
+    public void untar() throws IOException {
+        try (BufferedInputStream inputStream = new BufferedInputStream(getTarStream()); //
+            TarArchiveInputStream tar = new TarArchiveInputStream( //
+                isGzip() ? new GzipCompressorInputStream(inputStream) : inputStream)) {
+            ArchiveEntry entry;
+            while ((entry = tar.getNextEntry()) != null) {
+                Path extractTo = getDestination().resolve(entry.getName());
+                if (entry.isDirectory()) {
+                    Files.createDirectories(extractTo);
+                } else {
+                    Files.copy(tar, extractTo, StandardCopyOption.REPLACE_EXISTING);
+                }
+            }
+        }
+    }
+}

libraries-apache-commons-2/src/main/java/com/baeldung/commons/untar/impl/TarExtractorVfs.java

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+package com.baeldung.commons.untar.impl;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.nio.file.StandardCopyOption;
+
+import org.apache.commons.vfs2.FileContent;
+import org.apache.commons.vfs2.FileObject;
+import org.apache.commons.vfs2.FileSystemManager;
+import org.apache.commons.vfs2.FileType;
+import org.apache.commons.vfs2.VFS;
+
+import com.baeldung.commons.untar.TarExtractor;
+
+public class TarExtractorVfs extends TarExtractor {
+
+    public TarExtractorVfs(InputStream in, boolean gzip, Path destination) throws IOException {
+        super(in, gzip, destination);
+    }
+
+    @Override
+    public void untar() throws IOException {
+        Path tmpTar = Files.createTempFile("temp", isGzip() ? ".tar.gz" : ".tar");
+        Files.copy(getTarStream(), tmpTar, StandardCopyOption.REPLACE_EXISTING);
+
+        FileSystemManager fsManager = VFS.getManager();
+        String uri = String.format("%s:file://%s", isGzip() ? "tgz" : "tar", tmpTar);
+        FileObject tar = fsManager.resolveFile(uri);
+
+        for (FileObject entry : tar) {
+            Path extractTo = Paths.get(getDestination().toString(), entry.getName()
+                .getPath());
+
+            if (entry.isReadable() && entry.getType() == FileType.FILE) {
+                Files.createDirectories(extractTo.getParent());
+
+                try (FileContent content = entry.getContent(); InputStream stream = content.getInputStream()) {
+                    Files.copy(stream, extractTo, StandardCopyOption.REPLACE_EXISTING);
+                }
+            }
+        }
+
+        Files.delete(tmpTar);
+    }
+}

libraries-apache-commons-2/src/main/resources/logback.xml

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+<?xml version="1.0" encoding="UTF-8"?>
+<configuration>
+    <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
+        <encoder>
+            <pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n
+            </pattern>
+        </encoder>
+    </appender>
+
+    <root level="INFO">
+        <appender-ref ref="STDOUT" />
+    </root>
+</configuration>

libraries-apache-commons-2/src/test/java/com/baeldung/commons/untar/TarExtractorAntUnitTest.java

@@ -0,0 +1,40 @@
+package com.baeldung.commons.untar;
+
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.util.stream.Stream;
+
+import org.junit.Test;
+
+import com.baeldung.commons.untar.impl.TarExtractorAnt;
+
+public class TarExtractorAntUnitTest {
+
+    @Test
+    public void givenTarFile_whenUntar_thenExtractedToDestination() throws IOException {
+        Path destination = Paths.get("/tmp/ant");
+
+        new TarExtractorAnt(Resources.tarFile(), false, destination).untar();
+
+        try (Stream<Path> files = Files.list(destination)) {
+            assertTrue(files.findFirst()
+                .isPresent());
+        }
+    }
+
+    @Test
+    public void givenTarGzFile_whenUntar_thenExtractedToDestination() throws IOException {
+        Path destination = Paths.get("/tmp/ant-gz");
+
+        new TarExtractorAnt(Resources.tarGzFile(), true, destination).untar();
+
+        try (Stream<Path> files = Files.list(destination)) {
+            assertTrue(files.findFirst()
+                .isPresent());
+        }
+    }
+}

libraries-apache-commons-2/src/test/java/com/baeldung/commons/untar/TarExtractorCommonsCompressUnitTest.java

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+package com.baeldung.commons.untar;
+
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.util.stream.Stream;
+
+import org.junit.jupiter.api.Test;
+
+import com.baeldung.commons.untar.impl.TarExtractorCommonsCompress;
+
+public class TarExtractorCommonsCompressUnitTest {
+
+    @Test
+    public void givenTarFile_whenUntar_thenExtractedToDestination() throws IOException {
+        Path destination = Paths.get("/tmp/commons-compress");
+
+        new TarExtractorCommonsCompress(Resources.tarFile(), false, destination).untar();
+
+        try (Stream<Path> files = Files.list(destination)) {
+            assertTrue(files.findFirst()
+                .isPresent());
+        }
+    }
+
+    @Test
+    public void givenTarGzFile_whenUntar_thenExtractedToDestination() throws IOException {
+        Path destination = Paths.get("/tmp/commons-compress-gz");
+
+        new TarExtractorCommonsCompress(Resources.tarGzFile(), true, destination).untar();
+
+        try (Stream<Path> files = Files.list(destination)) {
+            assertTrue(files.findFirst()
+                .isPresent());
+        }
+    }
+}

libraries-apache-commons-2/src/test/java/com/baeldung/commons/untar/TarExtractorVfsUnitTest.java

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+package com.baeldung.commons.untar;
+
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.util.stream.Stream;
+
+import org.junit.Test;
+
+import com.baeldung.commons.untar.impl.TarExtractorVfs;
+
+public class TarExtractorVfsUnitTest {
+
+    @Test
+    public void givenTarFile_whenUntar_thenExtractedToDestination() throws IOException {
+        Path destination = Paths.get("/tmp/vfs");
+
+        new TarExtractorVfs(Resources.tarFile(), false, destination).untar();
+
+        try (Stream<Path> files = Files.list(destination)) {
+            assertTrue(files.findFirst()
+                .isPresent());
+        }
+    }
+
+    @Test
+    public void givenTarGzFile_whenUntar_thenExtractedToDestination() throws IOException {
+        Path destination = Paths.get("/tmp/vfs-gz");
+
+        new TarExtractorVfs(Resources.tarGzFile(), true, destination).untar();
+
+        try (Stream<Path> files = Files.list(destination)) {
+            assertTrue(files.findFirst()
+                .isPresent());
+        }
+    }
+}