Java Java类

此类实现了一个输入流过滤器，用于读取 ZIP 文件格式的文件。包括对压缩和未压缩条目的支持。
构造函数：

• ZipInputStream(InputStream in) ：创建一个新的 ZIP 输入流。
• ZipInputStream(InputStream in, Charset charset) :创建一个新的 ZIP 输入流

方法 ：

• int available() ：在当前条目数据到达 EOF 后返回 0，否则始终返回。
  程序不应指望此方法返回实际的字节数
  可以在没有阻塞的情况下读取。

  Syntax :public int available()
                throws IOException
  Overrides:
  available in class InflaterInputStream
  Returns:
  1 before EOF and 0 after EOF has reached for current entry. 
  Programs should not count on this method to return the actual number 
  of bytes that could be read without blocking.
  Throws:
  IOException 

• void close() ：关闭此输入流并释放与该流关联的所有系统资源。

  Syntax :public void close()
             throws IOException
  Overrides:
  close in class InflaterInputStream
  Throws:
  IOException

• void closeEntry() ：关闭当前 ZIP 条目并定位流以读取下一个条目。

  Syntax :public void closeEntry()
                  throws IOException
  Throws:
  ZipException 
  IOException 

• protected ZipEntry createZipEntry(String name) ：为指定的条目名称创建一个新的 ZipEntry 对象。

  Syntax :protected ZipEntry createZipEntry(String name)
  Parameters:
  name - the ZIP file entry name
  Returns:
  the ZipEntry just created

• ZipEntry getNextEntry() ：读取下一个 ZIP 文件条目并将流定位在条目数据的开头。

  Syntax :public ZipEntry getNextEntry()
                        throws IOException
  Returns:
  the next ZIP file entry, or null if there are no more entries
  Throws:
  ZipException 
  IOException 

• int read(byte[] b, int off, int len) ：从当前 ZIP 条目读取到字节数组中。如果 len 不为零，则该方法会阻塞，直到某些输入可用；否则，不读取任何字节并返回 0。

  Syntax :public int read(byte[] b,
         int off,
         int len)
           throws IOException
  Parameters:
  b - the buffer into which the data is read
  off - the start offset in the destination array b
  len - the maximum number of bytes read
  Returns:
  the actual number of bytes read, or -1 if the end of the entry is reached
  Throws:
  NullPointerException 
  IndexOutOfBoundsException 
  ZipException 
  IOException

• long skip(long n) ：跳过当前 ZIP 条目中指定的字节数。

  Syntax :public long skip(long n)
            throws IOException
  Parameters:
  n - the number of bytes to skip
  Returns:
  the actual number of bytes skipped
  Throws:
  ZipException
  IOException
  IllegalArgumentException 

//Java program demonstrating ZipInputStream methods
  
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.Arrays;
import java.util.jar.JarInputStream;
import java.util.zip.ZipEntry;
import java.util.zip.ZipInputStream;
class ZipInputStreamDemo extends ZipInputStream
{
    public ZipInputStreamDemo(InputStream in) 
    {
        super(in);
    }
  
    public static void main(String[] args) throws IOException
    {
        FileInputStream fis = new FileInputStream("Awesome CV.zip");
        ZipInputStream zis = new JarInputStream(fis);
        ZipInputStreamDemo obj = new ZipInputStreamDemo(zis);
  
        //illustrating createZipEntry()
        ZipEntry ze = obj.createZipEntry("ZipEntry");
        System.out.println(ze.getName());
  
        //illustrating getNextEntry()
        ZipEntry je = zis.getNextEntry();
        System.out.println(je.getName());
  
        //illustrating skip() method
        zis.skip(3);
  
        //illustrating closeEntry() method
        zis.closeEntry();
        zis.getNextEntry();
        byte b[] = new byte[10];
  
        //illustrating available() method
        //Reads up to byte.length bytes of data from this input stream
        if(zis.available() == 1)
            zis.read(b);
        System.out.println(Arrays.toString(b));
  
        //closing the stream
        zis.close();
    }
}

输出 ：

ZipEntry
awesome-cv.cls
[35, 32, 65, 119, 101, 115, 111, 109, 101, 32]