java unzip

这两天正好遇到解压问题，jdk里面正好有ZipEntity 可以使用，压缩包中有子目录的时候遇到了一些小的问题和坑记录一下。

必备知识:mkdir() 和mkdirs() 区别

文件夹的名字为newFolder, 假设 /home/admin/document/路径存在

mkdir() 该函数只能在已存在的文件夹下面建立新的文件夹，比如想创建 /home/admin/document/temp/newFolder 路径的文件夹, 如果/home/admin/document/temp/ 路径是存在的那么newFolder 就可以创建成功，如果/home/admin/document/temp/路径不存在则创建目录失败。

mkdirs() 该函数可以根据调用路径来建立路径 比如创建 /home/admin/document/temp/newFolder 程序编写者，不知道此文件路径/home/admin/document/temp 是否存在，就可以用此方法。该函数的原理是:如果父文件夹不存在并且最后一级子目录不存在，它就自动新建所有路径里写的文件夹；如果父文件夹存在，它就直接在已经存在的父文件夹下新建子文件夹。结果：/home/admin/document/temp/newFolder 先创建/home/admin/document/temp 文件夹 再创建 /home/admin/document/temp/newFolder/

完整的解压代码

package com.cn.passself.file;

import java.io.*;
import java.util.Enumeration;
import java.util.zip.ZipEntry;
import java.util.zip.ZipException;
import java.util.zip.ZipFile;
import java.util.zip.ZipInputStream;

/**

• Created by passself on 2018/7/11.

*/
public class ZipUtils {

public static void main(String[] args) {
    String zipFilePath = "/Users/xxx/Documents/temp/v6.zip";
    String outputFolder = "/Users/xxx/Documents/temp/res/";
    System.out.println(new File(zipFilePath).exists());
    unZipIt(zipFilePath,outputFolder);

    //测试2
    try {
        upZipFile(new File(zipFilePath),outputFolder);
    } catch (IOException e) {
        e.printStackTrace();
    }
}
/**
 * 解压文件
 * @param zipFilePath 解压文件路径
 * @param outputFolder 输出解压文件路径
 */
public static void unZipIt(String zipFilePath,String outputFolder){
    byte[] buffer = new byte[1024];

    File folder = new File(outputFolder);
    if (!folder.exists()){
        folder.mkdir();
    }
    try {
        //get the zip file content
        ZipInputStream zis = new ZipInputStream(new FileInputStream(zipFilePath));
        ZipEntry ze = zis.getNextEntry();
        while (ze != null){
            String fileName = ze.getName();
            File newFile = new File(outputFolder+File.separator+fileName);
            System.out.println("file unzip : "+ newFile.getAbsoluteFile());
            //create all non exists folders
            //else you will hit FileNotFoundException for compressed folder
            //大部分网络上的源码，这里没有判断子目录
            if (ze.isDirectory()){
                newFile.mkdirs();
            }else{
                new File(newFile.getParent()).mkdirs();
                FileOutputStream fos = new FileOutputStream(newFile);
                int len;
                while ((len = zis.read(buffer))!=-1){
                    fos.write(buffer,0,len);
                }
                fos.close();
            }
            ze = zis.getNextEntry();
        }
        zis.closeEntry();
        zis.close();
        System.out.println("Done");
    }catch (IOException e){
        e.printStackTrace();
    }
}

public static void unzip(File source, String out) throws IOException {
    try (ZipInputStream zis = new ZipInputStream(new FileInputStream(source))) {

        ZipEntry entry = zis.getNextEntry();

        while (entry != null) {

            File file = new File(out, entry.getName());

            if (entry.isDirectory()) {
                file.mkdirs();
            } else {
                File parent = file.getParentFile();

                if (!parent.exists()) {
                    parent.mkdirs();
                }

                try (BufferedOutputStream bos = new BufferedOutputStream(new FileOutputStream(file))) {

                    byte[] buffer = new byte[Math.toIntExact(entry.getSize())];

                    int location;

                    while ((location = zis.read(buffer)) != -1) {
                        bos.write(buffer, 0, location);
                    }
                }
            }
            entry = zis.getNextEntry();
        }
    }
}

/**
 * 把所有文件都直接解压到指定目录(忽略子文件夹)
 * @param zipFile
 * @param folderPath
 * @throws ZipException
 * @throws IOException
 */
public static void upZipFile(File zipFile, String folderPath) throws ZipException, IOException {
    File desDir = new File(folderPath);
    if (!desDir.exists()) {
        desDir.mkdirs();
    }
    ZipFile zf = new ZipFile(zipFile);
    for (Enumeration<?> entries = zf.entries(); entries.hasMoreElements(); ) {
        ZipEntry entry = ((ZipEntry) entries.nextElement());
        InputStream in = zf.getInputStream(entry);
        String str = folderPath;
        // str = new String(str.getBytes("8859_1"), "GB2312");
        File desFile = new File(str, java.net.URLEncoder.encode(entry.getName(), "UTF-8"));

        if (!desFile.exists()) {
            File fileParentDir = desFile.getParentFile();
            if (!fileParentDir.exists()) {
                fileParentDir.mkdirs();
            }
        }

        OutputStream out = new FileOutputStream(desFile);
        byte buffer[] = new byte[1024 * 1024];
        int realLength = in.read(buffer);
        while (realLength != -1) {
            out.write(buffer, 0, realLength);
            realLength = in.read(buffer);
        }

        out.close();
        in.close();

    }
}

}