Java中使用InputStream读入Jar/zip内容

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();
    }
  }
  
}