压缩是一种通过特定的算法来减小计算机文件大小的机制。这种机制是一种很方便的发明，尤其是对网络用户，因为它可以减小文件的字节总数，使文件能够通过较慢的互联网连接实现更快传输，此外还可以减少文件的磁盘占用空间。下面小编准备了关于Java的压缩与解压缩ZIP，提供给大家参考!
压缩的
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.util.zip.ZipEntry;
import java.util.zip.ZipOutputStream;
public class Zip {
static final int BUFFER = 2048;
public static void main(String argv[]) {
try {
BufferedInputStream origin = null;
FileOutputStream dest = new FileOutputStream("E:\\test\\myfiles.zip");
ZipOutputStream out = new ZipOutputStream(new BufferedOutputStream(
dest));
byte data[] = new byte[BUFFER];
File f = new File("e:\\test\\a\\");
File files[] = f.listFiles();
for (int i = 0; i < files.length; i++) {
FileInputStream fi = new FileInputStream(files[i]);
origin = new BufferedInputStream(fi, BUFFER);
ZipEntry entry = new ZipEntry(files[i].getName());
out.putNextEntry(entry);
int count;
while ((count = origin.read(data, 0, BUFFER)) != -1) {
out.write(data, 0, count);
}
origin.close();
}
out.close();
} catch (Exception e) {
e.printStackTrace();
}
}
}
解压缩的
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.util.Enumeration;
import java.util.zip.ZipEntry;
import java.util.zip.ZipFile;
public class UnZip {
static final int BUFFER = 2048;
public static void main(String argv[]) {
try {
String fileName = "E:\\test\\myfiles.zip";
String filePath = "E:\\test\\";
ZipFile zipFile = new ZipFile(fileName);
Enumeration emu = zipFile.entries();
int i=0;
while(emu.hasMoreElements()){
ZipEntry entry = (ZipEntry)emu.nextElement();
//会把目录作为一个file读出一次，所以只建立目录就可以，之下的文件还会被迭代到。
if (entry.isDirectory())
{
new File(filePath + entry.getName()).mkdirs();
continue;
}
BufferedInputStream bis = new BufferedInputStream(zipFile.getInputStream(entry));
File file = new File(filePath + entry.getName());
//加入这个的原因是zipfile读取文件是随机读取的，这就造成可能先读取一个文件
//而这个文件所在的目录还没有出现过，所以要建出目录来。
File parent = file.getParentFile();
if(parent != null && (!parent.exists())){
parent.mkdirs();
}
FileOutputStream fos = new FileOutputStream(file);
BufferedOutputStream bos = new BufferedOutputStream(fos,BUFFER);
int count;
byte data[] = new byte[BUFFER];
while ((count = bis.read(data, 0, BUFFER)) != -1)
{
bos.write(data, 0, count);
}
bos.flush();
bos.close();
bis.close();
}
zipFile.close();
} catch (Exception e) {
e.printStackTrace();
}
}
}
