Java壓縮類庫的使用

jopen 13年前發布 | 58K 次閱讀 Android Java開發

Java壓縮類庫的使用-1.總述

壓縮是編程中常見的技巧，多用于大文件壓縮，數據流壓縮等。在Java類庫中，內置了jar、ZIP、GZIP、ZLIB等的支持（見java.util.zip、java.util.jar包）。另外在Apache項目下Ant中ant.jar的org.apache.tools.tar、org.apache.tools.zip、org.apache.tools.bzip2分別提供了tar、zip、bzip2的支持；Apache commons compress項目里提供了對AR、BZIP、CPIO、GZP、TAR、ZIP的支持。7-zip提供了LZMA格式的壓縮（public domain），QuickLZ提供了quicklz格式的壓縮（GPL），oberhumer.com提供LZO格式的壓縮（GPL），hadoop-gpl-compression則對LZO的c實現用JNI進行包裝，提供更快捷的LZO壓縮。

　　嚴格來說，TAR、AR、CPIO并不屬于壓縮軟件，而是一種打包軟件，它能把很多文件、文件夾打包成一個文件，供壓縮程序壓縮。而咱們在windows中熟悉的zip、rar，嚴格的說是具備打包和壓縮功能的一種格式。

因為本人在項目中需主要需要應用壓縮工具對網絡中傳輸的數據流進行壓縮，因此重點關心對Stream的壓縮，而不關心對多個文件的壓縮，這在代碼中也會有所體現。因此，本系列的代碼一般僅適用于壓縮流或壓縮一個文件。

　　LZMA、QuickLZ、LZO因為提供的類庫不支持stream形式壓縮或提供的example太難看懂，故不作測試。這里還有一個需要提醒，Apache commons compress的tar、zip、bzip2來最初源于ant，但經過項目間遷移、演化，API及性能有所不同。

　　所有的格式均提供壓縮和解壓兩個方法，再次提醒這里所有代碼不適用于壓縮多個文件、文件夾。下面是抽象的壓縮、加壓縮類：

package study.inkfish.compress;
import java.io.File;
import java.io.IOException;
public abstract class Compress {
    public void compress(File srcFile, File destFile) {
        destFile.getParentFile().mkdirs();
        try {
            doCompress(srcFile, destFile);
        } catch (IOException ex) {
            ex.printStackTrace();
        }
    }
    public void decompress(File srcFile, File destDir) {
        destDir.mkdirs();
        try {
            doDecompress(srcFile, destDir);
        } catch (IOException ex) {
            ex.printStackTrace();
        }
    }
    protected int bufferLen = 1024 * 1024;//buffer size: 1MByte
    protected abstract void doCompress(File srcFile, File destFile) throws IOException;
    protected abstract void doDecompress(File srcFile, File destDir) throws IOException;
}

Java壓縮類庫的使用-2.JDK中的打包、壓縮類庫

package study.inkfish.compress;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.zip.DeflaterOutputStream;
import java.util.zip.InflaterInputStream;
import org.apache.commons.io.FilenameUtils;
import org.apache.commons.io.IOUtils;
/* JDK ZLIB壓縮： /
public class JdkZLIBCompress extends Compress {
    @Override
    protected void doCompress(File srcFile, File destFile) throws IOException {
        OutputStream out = null;
        InputStream is = null;
        try {
            is = new BufferedInputStream(new FileInputStream(srcFile), bufferLen);
            out = new DeflaterOutputStream(new BufferedOutputStream(new FileOutputStream(destFile), bufferLen));
            IOUtils.copy(is, out);
        } finally {
            IOUtils.closeQuietly(is);
            IOUtils.closeQuietly(out);
        }
    }
    @Override
    protected void doDecompress(File srcFile, File destDir) throws IOException {
        InputStream is = null;
        OutputStream os = null;
        try {
            File destFile = new File(destDir, FilenameUtils.getBaseName(srcFile.toString()));
            is = new InflaterInputStream(new BufferedInputStream(new FileInputStream(srcFile), bufferLen));
            os = new BufferedOutputStream(new FileOutputStream(destFile), bufferLen);
            IOUtils.copy(is, os);
        } finally {
            IOUtils.closeQuietly(is);
            IOUtils.closeQuietly(os);
        }
    }
}</pre>JDK ZIP壓縮（僅適用于壓縮一個文件）：

package study.inkfish.compress;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.zip.ZipEntry;
import java.util.zip.ZipInputStream;
import java.util.zip.ZipOutputStream;
import org.apache.commons.io.IOUtils;
public class JdkZipCompress extends Compress {
    @Override
    protected void doCompress(File srcFile, File destFile) throws IOException {
        ZipOutputStream zout = null;
        InputStream is = null;
        try {
            is = new BufferedInputStream(new FileInputStream(srcFile), bufferLen);
            zout = new ZipOutputStream(new BufferedOutputStream(new FileOutputStream(destFile), bufferLen));
            zout.putNextEntry(new ZipEntry(srcFile.getName()));
            IOUtils.copy(is, zout);
            zout.closeEntry();
        } finally {
            IOUtils.closeQuietly(is);
            IOUtils.closeQuietly(zout);
        }
    }
    @Override
    protected void doDecompress(File srcFile, File destDir) throws IOException {
        ZipInputStream is = null;
        try {
            is = new ZipInputStream(new BufferedInputStream(new FileInputStream(srcFile), bufferLen));
            ZipEntry entry = null;
            while ((entry = is.getNextEntry()) != null) {
                if (entry.isDirectory()) {
                    File directory = new File(destDir, entry.getName());
                    directory.mkdirs();
                    is.closeEntry();
                } else {
                    OutputStream os = null;
                    try {
                        os = new BufferedOutputStream(
                                new FileOutputStream(new File(destDir, entry.getName())), bufferLen);
                        IOUtils.copy(is, os);
                    } finally {
                        IOUtils.closeQuietly(os);
                    }
                    is.closeEntry();
                }
            }
        } finally {
            IOUtils.closeQuietly(is);
        }
    }
}


JDK GZIP壓縮：


package study.inkfish.compress;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.zip.GZIPInputStream;
import java.util.zip.GZIPOutputStream;
import org.apache.commons.io.FilenameUtils;
import org.apache.commons.io.IOUtils;
public class JdkGZIPCompress extends Compress {
    @Override
    protected void doCompress(File srcFile, File destFile) throws IOException {
        OutputStream out = null;
        InputStream is = null;
        try {
            is = new BufferedInputStream(new FileInputStream(srcFile), bufferLen);
            out = new GZIPOutputStream(new BufferedOutputStream(new FileOutputStream(destFile), bufferLen));
            IOUtils.copy(is, out);
        } finally {
            IOUtils.closeQuietly(is);
            IOUtils.closeQuietly(out);
        }
    }
    @Override
    protected void doDecompress(File srcFile, File destDir) throws IOException {
        InputStream is = null;
        OutputStream os = null;
        try {
            File destFile = new File(destDir, FilenameUtils.getBaseName(srcFile.toString()));
            is = new GZIPInputStream(new BufferedInputStream(new FileInputStream(srcFile), bufferLen));
            os = new BufferedOutputStream(new FileOutputStream(destFile), bufferLen);
            IOUtils.copy(is, os);
        } finally {
            IOUtils.closeQuietly(is);
            IOUtils.closeQuietly(os);
        }
    }
}
注：org.apache.commons.io包為Apache common io，項目首頁：http://commons.apache.org/io/，提供了IO操作的很多方便的方法，基于Apache 2.0 License，可用于商業用途。

 


Java壓縮類庫的使用-3.Apache Ant中的打包、壓縮類庫
這里需要關注的是BZIP2格式，經過測試，總是無法正確壓縮，原因未知，而apache commons bzip2格式的文件壓縮正常。Ant ZIP壓縮：

Ant ZIP壓縮：


package study.inkfish.compress;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Enumeration;
import org.apache.commons.io.IOUtils;
import org.apache.tools.zip.ZipEntry;
import org.apache.tools.zip.ZipFile;
import org.apache.tools.zip.ZipOutputStream;
public class AntZipCompress extends Compress {
    @Override
    protected void doCompress(File srcFile, File destFile) throws IOException {
        ZipOutputStream zout = null;
        InputStream is = null;
        try {
            is = new BufferedInputStream(new FileInputStream(srcFile), bufferLen);
            zout = new ZipOutputStream(new BufferedOutputStream(new FileOutputStream(destFile), bufferLen));
            zout.putNextEntry(new ZipEntry(srcFile.getName()));
            IOUtils.copy(is, zout);
            zout.closeEntry();
        } finally {
            IOUtils.closeQuietly(is);
            IOUtils.closeQuietly(zout);
        }
    }
    @Override
    protected void doDecompress(File srcFile, File destDir) throws IOException {
        ZipFile zipFile = new ZipFile(srcFile);
        try {
            @SuppressWarnings("unchecked")
            Enumeration<ZipEntry> enums = zipFile.getEntries();
            while (enums.hasMoreElements()) {
                ZipEntry entry = enums.nextElement();
                InputStream is = new BufferedInputStream(zipFile.getInputStream(entry), bufferLen);
                OutputStream os = null;
                try {
                    os = new BufferedOutputStream(new FileOutputStream(new File(destDir, entry.getName())), bufferLen);
                    IOUtils.copy(is, os);
                } finally {
                    IOUtils.closeQuietly(is);
                    IOUtils.closeQuietly(os);
                }
            }
        } finally {
            ZipFile.closeQuietly(zipFile);
        }
    }
}


Ant BZIP壓縮：


package study.inkfish.compress;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import org.apache.commons.io.FilenameUtils;
import org.apache.commons.io.IOUtils;
import org.apache.tools.bzip2.CBZip2InputStream;
import org.apache.tools.bzip2.CBZip2OutputStream;
public class AntBzip2Compress extends Compress {
    /**運行異常，無法正確打開*/
    @Override
    protected void doCompress(File srcFile, File destFile) throws IOException {
        OutputStream out = null;
        InputStream is = null;
        try {
            is = new BufferedInputStream(new FileInputStream(srcFile), bufferLen);
            out = new CBZip2OutputStream(new BufferedOutputStream(new FileOutputStream(destFile), bufferLen));
            IOUtils.copy(is, out);
        } finally {
            IOUtils.closeQuietly(is);
            IOUtils.closeQuietly(out);
        }
    }
    @Override
    protected void doDecompress(File srcFile, File destDir) throws IOException {
        InputStream is = null;
        OutputStream os = null;
        try {
            File destFile = new File(destDir, FilenameUtils.getBaseName(srcFile.toString()));
            is = new CBZip2InputStream(new BufferedInputStream(new FileInputStream(srcFile), bufferLen));
            os = new BufferedOutputStream(new FileOutputStream(destFile), bufferLen);
            IOUtils.copy(is, os);
        } finally {
            IOUtils.closeQuietly(is);
            IOUtils.closeQuietly(os);
        }
    }
}


Ant TAR打包：


package study.inkfish.compress;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import org.apache.commons.io.IOUtils;
import org.apache.tools.tar.TarEntry;
import org.apache.tools.tar.TarInputStream;
import org.apache.tools.tar.TarOutputStream;
public class AntTarCompress extends Compress {
    @Override
    protected void doCompress(File srcFile, File destFile) throws IOException {
        TarOutputStream out = null;
        InputStream is = null;
        try {
            is = new BufferedInputStream(new FileInputStream(srcFile), bufferLen);
            out = new TarOutputStream(new BufferedOutputStream(new FileOutputStream(destFile), bufferLen));
            TarEntry entry = new TarEntry(srcFile.getName());
            entry.setSize(srcFile.length());
            out.putNextEntry(entry);
            IOUtils.copy(is, out);
            out.closeEntry();
        } finally {
            IOUtils.closeQuietly(is);
            IOUtils.closeQuietly(out);
        }
    }
    @Override
    protected void doDecompress(File srcFile, File destDir) throws IOException {
        TarInputStream is = null;
        try {
            is = new TarInputStream(new BufferedInputStream(new FileInputStream(srcFile), bufferLen));
            TarEntry entry = null;
            while ((entry = is.getNextEntry()) != null) {
                if (entry.isDirectory()) {
                    File directory = new File(destDir, entry.getName());
                    directory.mkdirs();
                } else {
                    BufferedOutputStream bos = null;
                    try {
                        byte[] buffer = new byte[1024 * 512];//512k buffer
                        bos = new BufferedOutputStream(new FileOutputStream(
                                new File(destDir, entry.getName())), buffer.length);
                        int len;
                        long size = entry.getSize();
                        while (size > 0) {
                            if (size < buffer.length) {
                                len = is.read(buffer, 0, (int) size);
                                size -= len;
                            } else {
                                len = is.read(buffer);
                                size -= len;
                            }
                            bos.write(buffer, 0, len);
                        }
                    } finally {
                        IOUtils.closeQuietly(bos);
                    }
                }
            }
        } finally {
            IOUtils.closeQuietly(is);
        }
    }
}



Java壓縮類庫的使用-4.Apache commons compress中的打包、壓縮類庫
Apache commons compress BZIP2壓縮：


package study.inkfish.compress;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import org.apache.commons.compress.compressors.gzip.GzipCompressorInputStream;
import org.apache.commons.compress.compressors.gzip.GzipCompressorOutputStream;
import org.apache.commons.io.FilenameUtils;
import org.apache.commons.io.IOUtils;
public class CommonsBZip2Compress extends Compress {
    @Override
    protected void doCompress(File srcFile, File destFile) throws IOException {
        OutputStream out = null;
        InputStream is = null;
        try {
            is = new BufferedInputStream(new FileInputStream(srcFile), bufferLen);
            out = new GzipCompressorOutputStream(new BufferedOutputStream(new FileOutputStream(destFile), bufferLen));
            IOUtils.copy(is, out);
        } finally {
            IOUtils.closeQuietly(is);
            IOUtils.closeQuietly(out);
        }
    }
    @Override
    protected void doDecompress(File srcFile, File destDir) throws IOException {
        InputStream is = null;
        OutputStream os = null;
        try {
            File destFile = new File(destDir, FilenameUtils.getBaseName(srcFile.toString()));
            is = new GzipCompressorInputStream(new BufferedInputStream(new FileInputStream(srcFile), bufferLen));
            os = new BufferedOutputStream(new FileOutputStream(destFile), bufferLen);
            IOUtils.copy(is, os);
        } finally {
            IOUtils.closeQuietly(is);
            IOUtils.closeQuietly(os);
        }
    }
}


Apache commons compress GZIP壓縮：


package study.inkfish.compress;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import org.apache.commons.compress.compressors.bzip2.BZip2CompressorInputStream;
import org.apache.commons.compress.compressors.bzip2.BZip2CompressorOutputStream;
import org.apache.commons.io.FilenameUtils;
import org.apache.commons.io.IOUtils;
public class CommonsGZIPCompress extends Compress {
    @Override
    protected void doCompress(File srcFile, File destFile) throws IOException {
        OutputStream out = null;
        InputStream is = null;
        try {
            is = new BufferedInputStream(new FileInputStream(srcFile), bufferLen);
            out = new BZip2CompressorOutputStream(new BufferedOutputStream(new FileOutputStream(destFile), bufferLen));
            IOUtils.copy(is, out);
        } finally {
            IOUtils.closeQuietly(is);
            IOUtils.closeQuietly(out);
        }
    }
    @Override
    protected void doDecompress(File srcFile, File destDir) throws IOException {
        InputStream is = null;
        OutputStream os = null;
        try {
            File destFile = new File(destDir, FilenameUtils.getBaseName(srcFile.toString()));
            is = new BZip2CompressorInputStream(new BufferedInputStream(new FileInputStream(srcFile), bufferLen));
            os = new BufferedOutputStream(new FileOutputStream(destFile), bufferLen);
            IOUtils.copy(is, os);
        } finally {
            IOUtils.closeQuietly(is);
            IOUtils.closeQuietly(os);
        }
    }
}


Apache commons compress ZIP壓縮：


package study.inkfish.compress;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import org.apache.commons.compress.archivers.zip.ZipArchiveEntry;
import org.apache.commons.compress.archivers.zip.ZipArchiveInputStream;
import org.apache.commons.compress.archivers.zip.ZipArchiveOutputStream;
import org.apache.commons.io.IOUtils;
public class CommonsZipCompress extends Compress {
    /**用于單文件壓縮*/
    @Override
    protected void doCompress(File srcFile, File destFile) throws IOException {
        ZipArchiveOutputStream out = null;
        InputStream is = null;
        try {
            is = new BufferedInputStream(new FileInputStream(srcFile), bufferLen);
            out = new ZipArchiveOutputStream(new BufferedOutputStream(new FileOutputStream(destFile), bufferLen));
            ZipArchiveEntry entry = new ZipArchiveEntry(srcFile.getName());
            entry.setSize(srcFile.length());
            out.putArchiveEntry(entry);
            IOUtils.copy(is, out);
            out.closeArchiveEntry();
        } finally {
            IOUtils.closeQuietly(is);
            IOUtils.closeQuietly(out);
        }
    }
    @Override
    protected void doDecompress(File srcFile, File destDir) throws IOException {
        ZipArchiveInputStream is = null;
        try {
            is = new ZipArchiveInputStream(new BufferedInputStream(new FileInputStream(srcFile), bufferLen));
            ZipArchiveEntry entry = null;
            while ((entry = is.getNextZipEntry()) != null) {
                if (entry.isDirectory()) {
                    File directory = new File(destDir, entry.getName());
                    directory.mkdirs();
                } else {
                    OutputStream os = null;
                    try {
                        os = new BufferedOutputStream(
                                new FileOutputStream(new File(destDir, entry.getName())), bufferLen);
                        IOUtils.copy(is, os);
                    } finally {
                        IOUtils.closeQuietly(os);
                    }
                }
            }
        } finally {
            IOUtils.closeQuietly(is);
        }
    }
}


Apache commons compress AR打包：


package study.inkfish.compress;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import org.apache.commons.compress.archivers.ar.ArArchiveEntry;
import org.apache.commons.compress.archivers.ar.ArArchiveInputStream;
import org.apache.commons.compress.archivers.ar.ArArchiveOutputStream;
import org.apache.commons.io.IOUtils;
public class CommonsArCompress extends Compress {
    @Override
    protected void doCompress(File srcFile, File destFile) throws IOException {
        ArArchiveOutputStream zout = null;
        InputStream is = null;
        try {
            is = new BufferedInputStream(new FileInputStream(srcFile), bufferLen);
            zout = new ArArchiveOutputStream(new BufferedOutputStream(new FileOutputStream(destFile), bufferLen));
            zout.putArchiveEntry(new ArArchiveEntry(srcFile, srcFile.getName()));
            IOUtils.copy(is, zout);
            zout.closeArchiveEntry();
        } finally {
            IOUtils.closeQuietly(is);
            IOUtils.closeQuietly(zout);
        }
    }
    @Override
    protected void doDecompress(File srcFile, File destDir) throws IOException {
        ArArchiveInputStream is = null;
        try {
            is = new ArArchiveInputStream(new BufferedInputStream(new FileInputStream(srcFile), bufferLen));
            ArArchiveEntry entry = null;
            while ((entry = is.getNextArEntry()) != null) {
                if (entry.isDirectory()) {
                    File directory = new File(destDir, entry.getName());
                    directory.mkdirs();
                } else {
                    BufferedOutputStream bos = null;
                    try {
                        byte[] buffer = new byte[bufferLen];
                        bos = new BufferedOutputStream(new FileOutputStream(
                                new File(destDir, entry.getName())), bufferLen);
                        int len;
                        long size = entry.getSize();
                        while (size > 0) {
                            if (size < bufferLen) {
                                len = is.read(buffer, 0, (int) size);
                                size -= len;
                            } else {
                                len = is.read(buffer);
                                size -= len;
                            }
                            bos.write(buffer, 0, len);
                        }
                    } finally {
                        IOUtils.closeQuietly(bos);
                    }
                }
            }
        } finally {
            IOUtils.closeQuietly(is);
        }
    }
}


Apache commons compress CPIO打包：


package study.inkfish.compress;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import org.apache.commons.compress.archivers.cpio.CpioArchiveEntry;
import org.apache.commons.compress.archivers.cpio.CpioArchiveInputStream;
import org.apache.commons.compress.archivers.cpio.CpioArchiveOutputStream;
import org.apache.commons.io.IOUtils;
public class CommonsCPIOCompress extends Compress {
    @Override
    protected void doCompress(File srcFile, File destFile) throws IOException {
        CpioArchiveOutputStream out = null;
        InputStream is = null;
        try {
            is = new BufferedInputStream(new FileInputStream(srcFile), bufferLen);
            out = new CpioArchiveOutputStream(new BufferedOutputStream(new FileOutputStream(destFile), bufferLen));
            out.putArchiveEntry(new CpioArchiveEntry(srcFile, srcFile.getName()));
            IOUtils.copy(is, out);
            out.closeArchiveEntry();
        } finally {
            IOUtils.closeQuietly(is);
            IOUtils.closeQuietly(out);
        }
    }
    @Override
    protected void doDecompress(File srcFile, File destDir) throws IOException {
        CpioArchiveInputStream is = null;
        try {
            is = new CpioArchiveInputStream(new BufferedInputStream(new FileInputStream(srcFile), bufferLen));
            CpioArchiveEntry entry = null;
            while ((entry = is.getNextCPIOEntry()) != null) {
                if (entry.isDirectory()) {
                    File directory = new File(destDir, entry.getName());
                    directory.mkdirs();
                } else {
                    BufferedOutputStream bos = null;
                    try {
                        byte[] buffer = new byte[bufferLen];
                        bos = new BufferedOutputStream(new FileOutputStream(
                                new File(destDir, entry.getName())), bufferLen);
                        int len;
                        long size = entry.getSize();
                        while (size > 0) {
                            if (size < bufferLen) {
                                len = is.read(buffer, 0, (int) size);
                                size -= len;
                            } else {
                                len = is.read(buffer);
                                size -= len;
                            }
                            bos.write(buffer, 0, len);
                        }
                    } finally {
                        IOUtils.closeQuietly(bos);
                    }
                }
            }
        } finally {
            IOUtils.closeQuietly(is);
        }
    }
}


Apache commons compress TAR打包：


package study.inkfish.compress;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import org.apache.commons.compress.archivers.tar.TarArchiveEntry;
import org.apache.commons.compress.archivers.tar.TarArchiveInputStream;
import org.apache.commons.compress.archivers.tar.TarArchiveOutputStream;
import org.apache.commons.io.IOUtils;
public class CommonsTarCompress extends Compress {
    @Override
    protected void doCompress(File srcFile, File destFile) throws IOException {
        TarArchiveOutputStream out = null;
        InputStream is = null;
        try {
            is = new BufferedInputStream(new FileInputStream(srcFile), bufferLen);
            out = new TarArchiveOutputStream(new BufferedOutputStream(new FileOutputStream(destFile), bufferLen));
            TarArchiveEntry entry = new TarArchiveEntry(srcFile.getName());
            entry.setSize(srcFile.length());
            out.putArchiveEntry(entry);
            IOUtils.copy(is, out);
            out.closeArchiveEntry();
        } finally {
            IOUtils.closeQuietly(is);
            IOUtils.closeQuietly(out);
        }
    }
    @Override
    protected void doDecompress(File srcFile, File destDir) throws IOException {
        TarArchiveInputStream is = null;
        try {
            is = new TarArchiveInputStream(new BufferedInputStream(new FileInputStream(srcFile), bufferLen));
            TarArchiveEntry entry = null;
            while ((entry = is.getNextTarEntry()) != null) {
                if (entry.isDirectory()) {
                    File directory = new File(destDir, entry.getName());
                    directory.mkdirs();
                } else {
                    BufferedOutputStream bos = null;
                    try {
                        byte[] buffer = new byte[bufferLen];
                        bos = new BufferedOutputStream(new FileOutputStream(
                                new File(destDir, entry.getName())), bufferLen);
                        int len;
                        long size = entry.getSize();
                        while (size > 0) {
                            if (size < bufferLen) {
                                len = is.read(buffer, 0, (int) size);
                                size -= len;
                            } else {
                                len = is.read(buffer);
                                size -= len;
                            }
                            bos.write(buffer, 0, len);
                        }
                    } finally {
                        IOUtils.closeQuietly(bos);
                    }
                }
            }
        } finally {
            IOUtils.closeQuietly(is);
        }
    }
}




來源（http://blog.csdn.net/inkfish）。

本文由用戶 jopen 自行上傳分享，僅供網友學習交流。所有權歸原作者，若您的權利被侵害，請聯系管理員。

轉載本站原創文章，請注明出處，并保留原始鏈接、圖片水印。

本站是一個以用戶分享為主的開源技術平臺，歡迎各類分享！

本文地址：http://www.baiduhome.net/lib/view/open1349924139010.html

Android Java開發

Java壓縮類庫的使用

Java壓縮類庫的使用-1.總述

Java壓縮類庫的使用-2.JDK中的打包、壓縮類庫

相關經驗

相關資訊

相關文檔

目錄