根据系统本身功能进行解压
优点:无需导入另外的jar包,需要自己思考解压流程,比较复杂
缺点:不能解压加密的zip文件
/**
* 解压操作(包含子目录和文件)
* @param zipFile
* @param targetDir
* @return
*/
private int Unzip(String zipFile, String targetDir) {
int BUFFER = 4096; //这里缓冲区我们使用4KB,
ZipFile zipf = null;
try {
zipf = new ZipFile(zipFile);
}catch (Exception e){
e.printStackTrace();
return 0;
}
Enumeration zList = zipf.entries();
ZipEntry ze = null;
byte[] buf = new byte[BUFFER];
while (zList.hasMoreElements()) {
ze = (ZipEntry) zList.nextElement();
// 列举的压缩文件里面的各个文件,判断是否为目录
if (ze.isDirectory()) {
String dirstr = targetDir + ze.getName();
dirstr.trim();
File f = new File(dirstr);
f.mkdir();
continue;
}
OutputStream os = null;
FileOutputStream fos = null;
// ze.getName()会返回 script/start.script这样的,是为了返回实体的File
File realFile = getRealFileName(targetDir, ze.getName());
try {
fos = new FileOutputStream(realFile);
} catch (FileNotFoundException e) {
return 1;
}
os = new BufferedOutputStream(fos);
InputStream is = null;
try {
is = new BufferedInputStream(zipf.getInputStream(ze));
} catch (IOException e) {
return 2;
}
int readLen = 0;
// 进行一些内容复制操作
try {
while ((readLen = is.read(buf, 0, 1024)) != -1) {
os.write(buf, 0, readLen);
}
} catch (IOException e) {
return 3;
}
try {
is.close();
os.close();
} catch (IOException e) {
return 4;
}
}
try {
zipf.close();
} catch (IOException e) {
return 5;
}
return 6;
}
/**
* 给定根目录,返回一个相对路径所对应的实际文件名.
*
* @param baseDir
* 指定根目录
* @param absFileName
* 相对路径名,来自于ZipEntry中的name
* @return java.io.File 实际的文件
*/
public static File getRealFileName(String baseDir, String absFileName) {
absFileName = absFileName.replace("\\", "/");
String[] dirs = absFileName.split("/");
File ret = new File(baseDir);
String substr = null;
if (dirs.length > 1) {
for (int i = 0; i < dirs.length - 1; i++) {
substr = dirs[i];
ret = new File(ret, substr);
}
if (!ret.exists())
ret.mkdirs();
substr = dirs[dirs.length - 1];
ret = new File(ret, substr);
return ret;
} else {
ret = new File(ret, absFileName);
}
return ret;
}