Java中使用InputStream讀入Jar/zip內容__Java

因為項目需要，要把一個zip/jar檔案讀入到後台伺服器上，前台使用者選擇好zip/jar檔案

以後，upload檔案之後，從JarFile對象中迴圈讀取JarEntry對象，然後根據JarFile的

API使用jarFile.getInputStream(JarEntry jarEntry)來讀取每個JarEntry的內容。

可是最近他們想把檔案讀入變成基於inputstream的直接讀取，從http請求中擷取

inputstream之後可以直接讀入。這樣問題就來，怎麼從流中知道每個JarEntry對象

一番研究之後，有了下面的代碼：

package com.gloomyfish.image.study;import java.io.BufferedInputStream;import java.io.ByteArrayInputStream;import java.io.ByteArrayOutputStream;import java.io.File;import java.io.FileInputStream;import java.io.IOException;import java.io.InputStream;import java.util.HashMap;import java.util.Iterator;import java.util.jar.JarEntry;import java.util.jar.JarInputStream;import java.util.jar.Manifest;public class JarFileReader {private JarInputStream jarInput;private HashMap<String, ByteArrayOutputStream> entriesStreamMap;public JarFileReader(InputStream in) throws IOException {jarInput = new JarInputStream(in);entriesStreamMap = new HashMap<String, ByteArrayOutputStream>();}public void readEntries() throws IOException {JarEntry entry = jarInput.getNextJarEntry();String manifestEntry = null;while(entry != null) {System.out.println("Entry Name = " + entry.getName());if("jp/co/sony/csl/nielsen/phoenix/objectremoval/Mark.class".equals(entry.getName())) {manifestEntry = entry.getName();copyInputStream(jarInput, entry.getName());}entry = jarInput.getNextJarEntry();}System.out.println("Now!! + get jar entry inputstream again...");InputStream inputStream = getCopy(manifestEntry);System.out.println(inputStream.read());}public void copyInputStream(InputStream in, String entryName) throws IOException {if(!entriesStreamMap.containsKey(entryName)) {ByteArrayOutputStream _copy = new ByteArrayOutputStream();int read = 0;int chunk = 0;byte[] data = new byte[256];while(-1 != (chunk = in.read(data))){read += data.length;_copy.write(data, 0, chunk);}entriesStreamMap.put(entryName, _copy);}}public InputStream getCopy(String entryName) {ByteArrayOutputStream _copy = entriesStreamMap.get(entryName);return (InputStream)new ByteArrayInputStream(_copy.toByteArray());}public static void main(String[] args) {File jarFile = new File("D:\\agriculture\\clickremoval.jar");try {InputStream in = new BufferedInputStream(new FileInputStream(jarFile));JarFileReader reader = new JarFileReader(in);reader.readEntries();} catch (IOException e) {e.printStackTrace();}}}