java文本压缩算法_java 什么算法压缩文件最小

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已经匿名di用户   2022-5-29 19:38   1619   0

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有三种方式实现java压缩:

1、jdk自带的包java.util.zip.ZipOutputStream,不足之处,文件(夹)名称32313133353236313431303231363533e59b9ee7ad9431333363393666带中文时,出现乱码问题,实现代码如下:

/**

* 功能:把 sourceDir 目录下的所有文件进行 zip 格式的压缩,保存为指定 zip 文件

* @param sourceDir 如果是目录,eg:D:\\MyEclipse\\first\\testFile,则压缩目录下所有文件;

* 如果是文件,eg:D:\\MyEclipse\\first\\testFile\\aa.zip,则只压缩本文件

* @param zipFile 最后压缩的文件路径和名称,eg:D:\\MyEclipse\\first\\testFile\\aa.zip

*/

public File doZip(String sourceDir, String zipFilePath) throws IOException {

File file = new File(sourceDir);

File zipFile = new File(zipFilePath);

ZipOutputStream zos = null;

try {

// 创建写出流操作

OutputStream os = new FileOutputStream(zipFile);

BufferedOutputStream bos = new BufferedOutputStream(os);

zos = new ZipOutputStream(bos);

String basePath = null;

// 获取目录

if(file.isDirectory()) {

basePath = file.getPath();

}else {

basePath = file.getParent();

}

zipFile(file, basePath, zos);

}finally {

if(zos != null) {

zos.closeEntry();

zos.close();

}

}

return zipFile;

}

/**

* @param source 源文件

* @param basePath

* @param zos

*/

private void zipFile(File source, String basePath, ZipOutputStream zos)

throws IOException {

File[] files = null;

if (source.isDirectory()) {

files = source.listFiles();

} else {

files = new File[1];

files[0] = source;

}

InputStream is = null;

String pathName;

byte[] buf = new byte[1024];

int length = 0;

try{

for(File file : files) {

if(file.isDirectory()) {

pathName = file.getPath().substring(basePath.length() + 1) + "/";

zos.putNextEntry(new ZipEntry(pathName));

zipFile(file, basePath, zos);

}else {

pathName = file.getPath().substring(basePath.length() + 1);

is = new FileInputStream(file);

BufferedInputStream bis = new BufferedInputStream(is);

zos.putNextEntry(new ZipEntry(pathName));

while ((length = bis.read(buf)) > 0) {

zos.write(buf, 0, length);

}

}

}

}finally {

if(is != null) {

is.close();

}

}

}

2、使用org.apache.tools.zip.ZipOutputStream,代码如下,

package net.szh.zip;

import java.io.BufferedInputStream;

import java.io.File;

import java.io.FileInputStream;

import java.io.FileOutputStream;

import java.util.zip.CRC32;

import java.util.zip.CheckedOutputStream;

import org.apache.tools.zip.ZipEntry;

import org.apache.tools.zip.ZipOutputStream;

public class ZipCompressor {

static final int BUFFER = 8192;

private File zipFile;

public ZipCompressor(String pathName) {

zipFile = new File(pathName);

}

public void compress(String srcPathName) {

File file = new File(srcPathName);

if (!file.exists())

throw new RuntimeException(srcPathName + "不存在!");

try {

FileOutputStream fileOutputStream = new FileOutputStream(zipFile);

CheckedOutputStream cos = new CheckedOutputStream(fileOutputStream,

new CRC32());

ZipOutputStream out = new ZipOutputStream(cos);

String basedir = "";

compress(file, out, basedir);

out.close();

} catch (Exception e) {

throw new RuntimeException(e);

}

}

private void compress(File file, ZipOutputStream out, String basedir) {

/* 判断是目录还是文件 */

if (file.isDirectory()) {

System.out.println("压缩:" + basedir + file.getName());

this.compressDirectory(file, out, basedir);

} else {

System.out.println("压缩:" + basedir + file.getName());

this.compressFile(file, out, basedir);

}

}

/** 压缩一个目录 */

private void compressDirectory(File dir, ZipOutputStream out, String basedir) {

if (!dir.exists())

return;

File[] files = dir.listFiles();

for (int i = 0; i < files.length; i++) {

/* 递归 */

compress(files[i], out, basedir + dir.getName() + "/");

}

}

/** 压缩一个文件 */

private void compressFile(File file, ZipOutputStream out, String basedir) {

if (!file.exists()) {

return;

}

try {

BufferedInputStream bis = new BufferedInputStream(

new FileInputStream(file));

ZipEntry entry = new ZipEntry(basedir + file.getName());

out.putNextEntry(entry);

int count;

byte data[] = new byte[BUFFER];

while ((count = bis.read(data, 0, BUFFER)) != -1) {

out.write(data, 0, count);

}

bis.close();

} catch (Exception e) {

throw new RuntimeException(e);

}

}

}

3、可以用ant中的org.apache.tools.ant.taskdefs.Zip来实现,更加简单。

package net.szh.zip;

import java.io.File;

import org.apache.tools.ant.Project;

import org.apache.tools.ant.taskdefs.Zip;

import org.apache.tools.ant.types.FileSet;

public class ZipCompressorByAnt {

private File zipFile;

public ZipCompressorByAnt(String pathName) {

zipFile = new File(pathName);

}

public void compress(String srcPathName) {

File srcdir = new File(srcPathName);

if (!srcdir.exists())

throw new RuntimeException(srcPathName + "不存在!");

Project prj = new Project();

Zip zip = new Zip();

zip.setProject(prj);

zip.setDestFile(zipFile);

FileSet fileSet = new FileSet();

fileSet.setProject(prj);

fileSet.setDir(srcdir);

//fileSet.setIncludes("**/*.java"); 包括哪些文件或文件夹 eg:zip.setIncludes("*.java");

//fileSet.setExcludes(...); 排除哪些文件或文件夹

zip.addFileset(fileSet);

zip.execute();

}

}

测试一下

package net.szh.zip;

public class TestZip {

public static void main(String[] args) {

ZipCompressor zc = new ZipCompressor("E:\\szhzip.zip");

zc.compress("E:\\test");

ZipCompressorByAnt zca = new ZipCompressorByAnt("E:\\szhzipant.zip");

zca.compress("E:\\test");

}

}

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