java实现服务器文件打包zip并下载的示例(边打包边下载)
作者:
使用该方法,可以即时打包文件,一边打包一边传输,不使用任何的缓存,让用户零等待!
/**
*
* mySocket 客户端 Socket
* @param file 待打包的文件夹或文件
* @param fileName 打包下载的文件名
* @throws IOException
*/
private void down(File file, String fileName) throws IOException {
OutputStream outputStream = mySocket.getOutputStream();
StringBuffer sb = new StringBuffer("HTTP/1.1 200 OK\r\n");
sb.append("Server: java/1.1\r\n");
sb.append("Content-Type:application/octet-stream;charset=UTF-8\r\n");
//sb.append("User-Agent: Mozilla/4.0 (compatible;MSIE6.0;Windows NT 5.0)\r\n");
sb.append("Content-Disposition: attachment; filename=" + fileName
+ "\r\n");
sb.append("Transfer-Encoding: chunked\r\n");
sb.append("Connection: Keep-Alive\r\n\r\n");
outputStream.write(sb.toString().getBytes());
outputStream.flush();
ZipCompressor zipCompressor = new ZipCompressor(new MyOutputStream(
outputStream));
zipCompressor.compress(file);
System.out.println("zip end");
System.out.println("write '0\\r\\n\\r\\n'");
outputStream.write("0\r\n\r\n".getBytes());//Transfer-Encoding: chunked传输结束标记
outputStream.flush();
outputStream.close();
System.out.println("download stop");
try {
mySocket.close();
} catch (Throwable t) {
}
}
package cn.liangjintang.webserver.zipFile;
import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.OutputStream;
import java.lang.reflect.Field;
import java.util.zip.CRC32;
import java.util.zip.CheckedOutputStream;
import java.util.zip.ZipEntry;
import java.util.zip.ZipOutputStream;
public class ZipCompressor {
static final int BUFFER = 8192;
private OutputStream outputStream;
public ZipCompressor(MyOutputStream outputStream) {
this.outputStream=outputStream;
}
public void compress(File file) {
if (!file.exists())
throw new RuntimeException(file.getAbsolutePath() + "不存在!");
try {
CheckedOutputStream cos = new CheckedOutputStream(outputStream,
new CRC32());
ZipOutputStream out = new ZipOutputStream(cos);
String basedir = "";
compress(file, out, basedir);
out.close();//必须关闭,这样才会写入zip的结束信息,否则zip文件不完整.若想继续写入,可重写outputStream.close()方法
} 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);
}
}
}
package cn.liangjintang.webserver.zipFile;
import java.io.FilterOutputStream;
import java.io.IOException;
import java.io.OutputStream;
public class MyOutputStream extends FilterOutputStream {
public MyOutputStream(OutputStream out) {
super(out);
}
final byte[] oneBytes = "1\r\n".getBytes();
final byte[] rnBytes = "\r\n".getBytes();
public void write(int b) throws IOException {
out.write(oneBytes);//字节数1+CRLF
out.write(b);//数据实体
out.write(rnBytes);//CRLF
}
public void write(byte[] b) throws IOException {
out.write(Integer.toHexString(b.length).getBytes());//字节数,十六进制
out.write(rnBytes);//CRLF
out.write(b);//数据实体
out.write(rnBytes);//CRLF
}
public void write(byte[] b, int off, int len) throws IOException {
out.write(Integer.toHexString(len - off).getBytes());//字节数,十六进制
out.write(rnBytes);//CRLF
out.write(b, off, len);//数据实体
out.write(rnBytes);//CRLF
}
/**
* 重写该方法,否则OutputStream会被关闭,其他的数据<br/>
* (如Transfer-Encoding: chunked传输结束标记)就不能再继续写入了
*/
public void close() throws IOException {
}
}