java.util.zip
Class ZipInputStream

java.lang.Object
  extended byjava.io.InputStream
      extended byjava.io.FilterInputStream
          extended byjava.util.zip.InflaterInputStream
              extended byjava.util.zip.ZipInputStream
All Implemented Interfaces:
ZipConstants
Direct Known Subclasses:
JarInputStream

public class ZipInputStream
extends InflaterInputStream
implements ZipConstants

This class implements an input stream filter for reading files in the ZIP file format. Includes support for both compressed and uncompressed entries.

Author:
David Connelly

Field Summary
private  byte[] b
           
static int CENATT
           
static int CENATX
           
static int CENCOM
           
static int CENCRC
           
static int CENDSK
           
static int CENEXT
           
static int CENFLG
           
static int CENHDR
           
static int CENHOW
           
static int CENLEN
           
static int CENNAM
           
static int CENOFF
           
static long CENSIG
           
static int CENSIZ
           
static int CENTIM
           
static int CENVEM
           
static int CENVER
           
private  boolean closed
           
private  CRC32 crc
           
private static int DEFLATED
           
static int ENDCOM
           
static int ENDHDR
           
static int ENDOFF
           
static long ENDSIG
           
static int ENDSIZ
           
static int ENDSUB
           
static int ENDTOT
           
private  ZipEntry entry
           
private  boolean entryEOF
           
static int EXTCRC
           
static int EXTHDR
           
static int EXTLEN
           
static long EXTSIG
           
static int EXTSIZ
           
static int LOCCRC
           
static int LOCEXT
           
static int LOCFLG
           
static int LOCHDR
           
static int LOCHOW
           
static int LOCLEN
           
static int LOCNAM
           
static long LOCSIG
           
static int LOCSIZ
           
static int LOCTIM
           
static int LOCVER
           
private  long remaining
           
private static int STORED
           
private  byte[] tmpbuf
           
 
Fields inherited from class java.util.zip.InflaterInputStream
buf, inf, len, usesDefaultInflater
 
Fields inherited from class java.io.FilterInputStream
in
 
Fields inherited from class java.io.InputStream
 
Constructor Summary
ZipInputStream(InputStream in)
          Creates a new ZIP input stream.
 
Method Summary
 int available()
          Returns 0 after EOF has reached for the current entry data, otherwise always return 1.
 void close()
          Closes the ZIP input stream.
 void closeEntry()
          Closes the current ZIP entry and positions the stream for reading the next entry.
protected  ZipEntry createZipEntry(String name)
          Creates a new ZipEntry object for the specified entry name.
private  void ensureOpen()
          Check to make sure that this stream has not been closed
private static int get16(byte[] b, int off)
           
private static long get32(byte[] b, int off)
           
 ZipEntry getNextEntry()
          Reads the next ZIP file entry and positions stream at the beginning of the entry data.
private static String getUTF8String(byte[] b, int off, int len)
           
 int read(byte[] b, int off, int len)
          Reads from the current ZIP entry into an array of bytes.
private  void readEnd(ZipEntry e)
           
private  void readFully(byte[] b, int off, int len)
           
private  ZipEntry readLOC()
           
 long skip(long n)
          Skips specified number of bytes in the current ZIP entry.
 
Methods inherited from class java.util.zip.InflaterInputStream
fill, read
 
Methods inherited from class java.io.FilterInputStream
mark, markSupported, read, reset
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Field Detail

entry

private ZipEntry entry

crc

private CRC32 crc

remaining

private long remaining

tmpbuf

private byte[] tmpbuf

STORED

private static final int STORED
See Also:
Constant Field Values

DEFLATED

private static final int DEFLATED
See Also:
Constant Field Values

closed

private boolean closed

entryEOF

private boolean entryEOF

b

private byte[] b

LOCSIG

public static final long LOCSIG
See Also:
Constant Field Values

EXTSIG

public static final long EXTSIG
See Also:
Constant Field Values

CENSIG

public static final long CENSIG
See Also:
Constant Field Values

ENDSIG

public static final long ENDSIG
See Also:
Constant Field Values

LOCHDR

public static final int LOCHDR
See Also:
Constant Field Values

EXTHDR

public static final int EXTHDR
See Also:
Constant Field Values

CENHDR

public static final int CENHDR
See Also:
Constant Field Values

ENDHDR

public static final int ENDHDR
See Also:
Constant Field Values

LOCVER

public static final int LOCVER
See Also:
Constant Field Values

LOCFLG

public static final int LOCFLG
See Also:
Constant Field Values

LOCHOW

public static final int LOCHOW
See Also:
Constant Field Values

LOCTIM

public static final int LOCTIM
See Also:
Constant Field Values

LOCCRC

public static final int LOCCRC
See Also:
Constant Field Values

LOCSIZ

public static final int LOCSIZ
See Also:
Constant Field Values

LOCLEN

public static final int LOCLEN
See Also:
Constant Field Values

LOCNAM

public static final int LOCNAM
See Also:
Constant Field Values

LOCEXT

public static final int LOCEXT
See Also:
Constant Field Values

EXTCRC

public static final int EXTCRC
See Also:
Constant Field Values

EXTSIZ

public static final int EXTSIZ
See Also:
Constant Field Values

EXTLEN

public static final int EXTLEN
See Also:
Constant Field Values

CENVEM

public static final int CENVEM
See Also:
Constant Field Values

CENVER

public static final int CENVER
See Also:
Constant Field Values

CENFLG

public static final int CENFLG
See Also:
Constant Field Values

CENHOW

public static final int CENHOW
See Also:
Constant Field Values

CENTIM

public static final int CENTIM
See Also:
Constant Field Values

CENCRC

public static final int CENCRC
See Also:
Constant Field Values

CENSIZ

public static final int CENSIZ
See Also:
Constant Field Values

CENLEN

public static final int CENLEN
See Also:
Constant Field Values

CENNAM

public static final int CENNAM
See Also:
Constant Field Values

CENEXT

public static final int CENEXT
See Also:
Constant Field Values

CENCOM

public static final int CENCOM
See Also:
Constant Field Values

CENDSK

public static final int CENDSK
See Also:
Constant Field Values

CENATT

public static final int CENATT
See Also:
Constant Field Values

CENATX

public static final int CENATX
See Also:
Constant Field Values

CENOFF

public static final int CENOFF
See Also:
Constant Field Values

ENDSUB

public static final int ENDSUB
See Also:
Constant Field Values

ENDTOT

public static final int ENDTOT
See Also:
Constant Field Values

ENDSIZ

public static final int ENDSIZ
See Also:
Constant Field Values

ENDOFF

public static final int ENDOFF
See Also:
Constant Field Values

ENDCOM

public static final int ENDCOM
See Also:
Constant Field Values
Constructor Detail

ZipInputStream

public ZipInputStream(InputStream in)
Creates a new ZIP input stream.

Parameters:
in - the actual input stream
Method Detail

ensureOpen

private void ensureOpen()
                 throws IOException
Check to make sure that this stream has not been closed

Throws:
IOException

getNextEntry

public ZipEntry getNextEntry()
                      throws IOException
Reads the next ZIP file entry and positions stream at the beginning of the entry data.

Returns:
the ZipEntry just read
Throws:
ZipException - if a ZIP file error has occurred
IOException - if an I/O error has occurred

closeEntry

public void closeEntry()
                throws IOException
Closes the current ZIP entry and positions the stream for reading the next entry.

Throws:
ZipException - if a ZIP file error has occurred
IOException - if an I/O error has occurred

available

public int available()
              throws IOException
Returns 0 after EOF has reached for the current entry data, otherwise always return 1.

Programs should not count on this method to return the actual number of bytes that could be read without blocking.

Overrides:
available in class InflaterInputStream
Returns:
1 before EOF and 0 after EOF has reached for current entry.
Throws:
IOException - if an I/O error occurs.

read

public int read(byte[] b,
                int off,
                int len)
         throws IOException
Reads from the current ZIP entry into an array of bytes. Blocks until some input is available.

Overrides:
read in class InflaterInputStream
Parameters:
b - the buffer into which the data is read
off - the start offset of the data
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:
ZipException - if a ZIP file error has occurred
IOException - if an I/O error has occurred

skip

public long skip(long n)
          throws IOException
Skips specified number of bytes in the current ZIP entry.

Overrides:
skip in class InflaterInputStream
Parameters:
n - the number of bytes to skip
Returns:
the actual number of bytes skipped
Throws:
ZipException - if a ZIP file error has occurred
IOException - if an I/O error has occurred
IllegalArgumentException - if n < 0

close

public void close()
           throws IOException
Closes the ZIP input stream.

Overrides:
close in class InflaterInputStream
Throws:
IOException - if an I/O error has occurred

readLOC

private ZipEntry readLOC()
                  throws IOException
Throws:
IOException

getUTF8String

private static String getUTF8String(byte[] b,
                                    int off,
                                    int len)

createZipEntry

protected ZipEntry createZipEntry(String name)
Creates a new ZipEntry object for the specified entry name.

Parameters:
name - the ZIP file entry name
Returns:
the ZipEntry just created

readEnd

private void readEnd(ZipEntry e)
              throws IOException
Throws:
IOException

readFully

private void readFully(byte[] b,
                       int off,
                       int len)
                throws IOException
Throws:
IOException

get16

private static final int get16(byte[] b,
                               int off)

get32

private static final long get32(byte[] b,
                                int off)