实例展示使用Java压缩和解压缩7z文件的方法

public byte[] lzmaZip(String xml) throws IOException{   BufferedInputStream inStream = new BufferedInputStream(new ByteArrayInputStream(xml.getBytes()));   ByteArrayOutputStream bos = new ByteArrayOutputStream();      boolean eos = true;     Encoder encoder = new Encoder();     encoder.SetEndMarkerMode(eos);     encoder.WriteCoderProperties(bos);     long fileSize = xml.length();     if (eos)       fileSize = -1;     for (int i = 0; i < 8; i++)       bos.write((int)(fileSize >>> (8 * i)) & 0xFF);     encoder.Code(inStream, bos, -1, -1, null);     return bos.toByteArray() ; } 

package core;import java.io.File;import java.io.FileNotFoundException;import java.io.FileOutputStream;import java.io.IOException;import java.io.RandomAccessFile;import java.util.Arrays;import net.sf.sevenzipjbinding.ExtractOperationResult;import net.sf.sevenzipjbinding.ISequentialOutStream;import net.sf.sevenzipjbinding.ISevenZipInArchive;import net.sf.sevenzipjbinding.SevenZip;import net.sf.sevenzipjbinding.SevenZipException;import net.sf.sevenzipjbinding.impl.RandomAccessFileInStream;import net.sf.sevenzipjbinding.simple.ISimpleInArchive;import net.sf.sevenzipjbinding.simple.ISimpleInArchiveItem;/**利用7zbinding*/public class UnZip {  void extractile(String filepath){     RandomAccessFile randomAccessFile = null;      ISevenZipInArchive inArchive = null;      try {        randomAccessFile = new RandomAccessFile(filepath, "r");        inArchive = SevenZip.openInArchive(null, // autodetect archive type            new RandomAccessFileInStream(randomAccessFile));        // Getting simple interface of the archive inArchive        ISimpleInArchive simpleInArchive = inArchive.getSimpleInterface();        System.out.println("  Hash  |  Size  | Filename");        System.out.println("----------+------------+---------");        for (final ISimpleInArchiveItem item : simpleInArchive.getArchiveItems()) {          final int[] hash = new int[] { 0 };          if (!item.isFolder()) {            ExtractOperationResult result;            final long[] sizeArray = new long[1];            result = item.extractSlow(new ISequentialOutStream() {              public int write(byte[] data) throws SevenZipException {                //Write to file                FileOutputStream fos;                try {                  File file = new File(item.getPath());                  //error occours below//                 file.getParentFile().mkdirs();                  fos = new FileOutputStream(file);                  fos.write(data);                  fos.close();                } catch (FileNotFoundException e) {                  // TODO Auto-generated catch block                  e.printStackTrace();                } catch (IOException e) {                  // TODO Auto-generated catch block                  e.printStackTrace();                }                hash[0] ^= Arrays.hashCode(data); // Consume data                sizeArray[0] += data.length;                return data.length; // Return amount of consumed data              }            });            if (result == ExtractOperationResult.OK) {              System.out.println(String.format("%9X | %10s | %s", //                   hash[0], sizeArray[0], item.getPath()));            } else {              System.err.println("Error extracting item: " + result);            }          }        }      } catch (Exception e) {        System.err.println("Error occurs: " + e);        e.printStackTrace();        System.exit(1);      } finally {        if (inArchive != null) {          try {            inArchive.close();          } catch (SevenZipException e) {            System.err.println("Error closing archive: " + e);          }        }        if (randomAccessFile != null) {          try {            randomAccessFile.close();          } catch (IOException e) {            System.err.println("Error closing file: " + e);          }        }      }  }}

unzip=new UnZip();unzip.extractile("a.7z");