java.util.jar.JarInputStream

All Implemented Interfaces:: Closeable, AutoCloseable

public class JarInputStream
extends ZipInputStream

The JarInputStream class is used to read the contents of a JAR file from any input stream. It extends the class java.util.zip.ZipInputStream with support for reading an optional Manifest entry. The Manifest can be used to store meta-information about the JAR file and its entries.

Since:: 1.2
See Also:: Manifest, ZipInputStream

Field Summary

Fields
Modifier and Type	Field	Description
`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`
`static int`	`ENDCOM`
`static int`	`ENDHDR`
`static int`	`ENDOFF`
`static long`	`ENDSIG`
`static int`	`ENDSIZ`
`static int`	`ENDSUB`
`static int`	`ENDTOT`
`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`

Fields declared in class java.util.zip.InflaterInputStream

buf, inf, len

Fields declared in class java.io.FilterInputStream

in

Constructor Summary

Constructors
Constructor	Description
`JarInputStream(InputStream in)`	Creates a new `JarInputStream` and reads the optional manifest.
`JarInputStream(InputStream in, boolean verify)`	Creates a new `JarInputStream` and reads the optional manifest.

Method Summary

Modifier and Type	Method	Description
`protected ZipEntry`	`createZipEntry(String name)`	Creates a new `JarEntry` (`ZipEntry`) for the specified JAR file entry name.
`Manifest`	`getManifest()`	Returns the `Manifest` for this JAR file, or `null` if none.
`ZipEntry`	`getNextEntry()`	Reads the next ZIP file entry and positions the stream at the beginning of the entry data.
`JarEntry`	`getNextJarEntry()`	Reads the next JAR file entry and positions the stream at the beginning of the entry data.
`int`	`read(byte[] b, int off, int len)`	Reads from the current JAR file entry into an array of bytes.

Methods declared in class java.util.zip.ZipInputStream

available, close, closeEntry, skip

Methods declared in class java.util.zip.InflaterInputStream

fill, mark, markSupported, read, reset

Methods declared in class java.io.FilterInputStream

read

Methods declared in class java.io.InputStream

nullInputStream, readAllBytes, readNBytes, readNBytes, skipNBytes, transferTo

Methods declared in class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details
- 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 Details
- JarInputStream
  
  public JarInputStream(InputStream in) throws IOException
  
  Creates a new JarInputStream and reads the optional manifest. If a manifest is present, also attempts to verify the signatures if the JarInputStream is signed.
  
  Parameters:
  
  in - the actual input stream
  
  Throws:
  
  IOException - if an I/O error has occurred
- JarInputStream
  
  public JarInputStream(InputStream in, boolean verify) throws IOException
  
  Creates a new JarInputStream and reads the optional manifest. If a manifest is present and verify is true, also attempts to verify the signatures if the JarInputStream is signed.
  
  Parameters:
  
  in - the actual input stream
  
  verify - whether or not to verify the JarInputStream if it is signed.
  
  Throws:
  
  IOException - if an I/O error has occurred
Method Details
- getManifest
  
  public Manifest getManifest()
  
  Returns the Manifest for this JAR file, or null if none.
  
  Returns:
  
  the Manifest for this JAR file, or null if none.
- getNextEntry
  
  public ZipEntry getNextEntry() throws IOException
  
  Reads the next ZIP file entry and positions the stream at the beginning of the entry data. If verification has been enabled, any invalid signature detected while positioning the stream for the next entry will result in an exception.
  
  Overrides:
  
  getNextEntry in class ZipInputStream
  
  Returns:
  
  the next ZIP file entry, or null if there are no more entries
  
  Throws:
  
  ZipException - if a ZIP file error has occurred
  
  IOException - if an I/O error has occurred
  
  SecurityException - if any of the jar file entries are incorrectly signed.
- getNextJarEntry
  
  public JarEntry getNextJarEntry() throws IOException
  
  Reads the next JAR file entry and positions the stream at the beginning of the entry data. If verification has been enabled, any invalid signature detected while positioning the stream for the next entry will result in an exception.
  
  Returns:
  
  the next JAR file entry, or null if there are no more entries
  
  Throws:
  
  ZipException - if a ZIP file error has occurred
  
  IOException - if an I/O error has occurred
  
  SecurityException - if any of the jar file entries are incorrectly signed.
- read
  
  public int read(byte[] b, int off, int len) throws IOException
  
  Reads from the current JAR file entry into an array of bytes. If len is not zero, the method blocks until some input is available; otherwise, no bytes are read and 0 is returned. If verification has been enabled, any invalid signature on the current entry will be reported at some point before the end of the entry is reached.
  
  Overrides:
  
  read in class ZipInputStream
  
  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 to read
  
  Returns:
  
  the actual number of bytes read, or -1 if the end of the entry is reached
  
  Throws:
  
  NullPointerException - If b is null.
  
  IndexOutOfBoundsException - If off is negative, len is negative, or len is greater than b.length - off
  
  ZipException - if a ZIP file error has occurred
  
  IOException - if an I/O error has occurred
  
  SecurityException - if any of the jar file entries are incorrectly signed.
  
  See Also:
  
  FilterInputStream.in
- createZipEntry
  
  protected ZipEntry createZipEntry(String name)
  
  Creates a new JarEntry (ZipEntry) for the specified JAR file entry name. The manifest attributes of the specified JAR file entry name will be copied to the new JarEntry.
  
  Overrides:
  
  createZipEntry in class ZipInputStream
  
  Parameters:
  
  name - the name of the JAR/ZIP file entry
  
  Returns:
  
  the JarEntry object just created

Class JarInputStream