/*
* @(#)ZipFile.java 1.82 08/04/17
*
* Copyright 2008 Sun Microsystems, Inc. All rights reserved.
* SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*/
package java.util.zip;
import java.io.InputStream;
import java.io.IOException;
import java.io.EOFException;
import java.io.File;
import java.util.Vector;
import java.util.Enumeration;
import java.util.NoSuchElementException;
/**
* This class is used to read entries from a zip file.
*
* <p> Unless otherwise noted, passing a <tt>null</tt> argument to a constructor
* or method in this class will cause a {@link NullPointerException} to be
* thrown.
*
* @version 1.78, 07/31/06
* @author David Connelly
*/
public
class ZipFile implements ZipConstants {
private long jzfile; // address of jzfile data
private String name; // zip file name
private int total; // total number of entries
private boolean closeRequested;
private static final int STORED = ZipEntry.STORED;
private static final int DEFLATED = ZipEntry.DEFLATED;
/**
* Mode flag to open a zip file for reading.
*/
public static final int OPEN_READ = 0x1;
/**
* Mode flag to open a zip file and mark it for deletion. The file will be
* deleted some time between the moment that it is opened and the moment
* that it is closed, but its contents will remain accessible via the
* <tt>ZipFile</tt> object until either the close method is invoked or the
* virtual machine exits.
*/
public static final int OPEN_DELETE = 0x4;
static {
/* Zip library is loaded from System.initializeSystemClass */
initIDs();
}
private static native void initIDs();
/**
* Opens a zip file for reading.
*
* <p>First, if there is a security
* manager, its <code>checkRead</code> method
* is called with the <code>name</code> argument
* as its argument to ensure the read is allowed.
*
* @param name the name of the zip file
* @throws ZipException if a ZIP format error has occurred
* @throws IOException if an I/O error has occurred
* @throws SecurityException if a security manager exists and its
* <code>checkRead</code> method doesn't allow read access to the file.
* @see SecurityManager#checkRead(java.lang.String)
*/
public ZipFile(String name) throws IOException {
this(new File(name), OPEN_READ);
}
/**
* Opens a new <code>ZipFile</code> to read from the specified
* <code>File</code> object in the specified mode. The mode argument
* must be either <tt>OPEN_READ</tt> or <tt>OPEN_READ | OPEN_DELETE</tt>.
*
* <p>First, if there is a security manager, its <code>checkRead</code>
* method is called with the <code>name</code> argument as its argument to
* ensure the read is allowed.
*
* @param file the ZIP file to be opened for reading
* @param mode the mode in which the file is to be opened
* @throws ZipException if a ZIP format error has occurred
* @throws IOException if an I/O error has occurred
* @throws SecurityException if a security manager exists and
* its <code>checkRead</code> method
* doesn't allow read access to the file,
* or its <code>checkDelete</code> method doesn't allow deleting
* the file when the <tt>OPEN_DELETE</tt> flag is set.
* @throws IllegalArgumentException if the <tt>mode</tt> argument is invalid
* @see SecurityManager#checkRead(java.lang.String)
* @since 1.3
*/
public ZipFile(File file, int mode) throws IOException {
if (((mode & OPEN_READ) == 0) ||
((mode & ~(OPEN_READ | OPEN_DELETE)) != 0)) {
throw new IllegalArgumentException("Illegal mode: 0x"+
Integer.toHexString(mode));
}
String name = file.getPath();
SecurityManager sm = System.getSecurityManager();
if (sm != null) {
sm.checkRead(name);
if ((mode & OPEN_DELETE) != 0) {
sm.checkDelete(name);
}
}
jzfile = open(name, mode, file.lastModified());
this.name = name;
this.total = getTotal(jzfile);
}
private static native long open(String name, int mode, long lastModified);
private static native int getTotal(long jzfile);
/**
* Opens a ZIP file for reading given the specified File object.
* @param file the ZIP file to be opened for reading
* @throws ZipException if a ZIP error has occurred
* @throws IOException if an I/O error has occurred
*/
public ZipFile(File file) throws ZipException, IOException {
this(file, OPEN_READ);
}
/**
* Returns the zip file entry for the specified name, or null
* if not found.
*
* @param name the name of the entry
* @return the zip file entry, or null if not found
* @throws IllegalStateException if the zip file has been closed
*/
public ZipEntry getEntry(String name) {
if (name == null) {
throw new NullPointerException("name");
}
long jzentry = 0;
synchronized (this) {
ensureOpen();
jzentry = getEntry(jzfile, name, true);
if (jzentry != 0) {
ZipEntry ze = new ZipEntry(name, jzentry);
freeEntry(jzfile, jzentry);
return ze;
}
}
return null;
}
private static native long getEntry(long jzfile, String name,
boolean addSlash);
// freeEntry releases the C jzentry struct.
private static native void freeEntry(long jzfile, long jzentry);
/**
* Returns an input stream for reading the contents of the specified
* zip file entry.
*
* <p> Closing this ZIP file will, in turn, close all input
* streams that have been returned by invocations of this method.
*
* @param entry the zip file entry
* @return the input stream for reading the contents of the specified
* zip file entry.
* @throws ZipException if a ZIP format error has occurred
* @throws IOException if an I/O error has occurred
* @throws IllegalStateException if the zip file has been closed
*/
public InputStream getInputStream(ZipEntry entry) throws IOException {
return getInputStream(entry.name);
}
/**
* Returns an input stream for reading the contents of the specified
* entry, or null if the entry was not found.
*/
private InputStream getInputStream(String name) throws IOException {
if (name == null) {
throw new NullPointerException("name");
}
long jzentry = 0;
ZipFileInputStream in = null;
synchronized (this) {
ensureOpen();
jzentry = getEntry(jzfile, name, false);
if (jzentry == 0) {
return null;
}
in = new ZipFileInputStream(jzentry);
}
final ZipFileInputStream zfin = in;
switch (getMethod(jzentry)) {
case STORED:
return zfin;
case DEFLATED:
// MORE: Compute good size for inflater stream:
long size = getSize(jzentry) + 2; // Inflater likes a bit of slack
if (size > 65536) size = 8192;
if (size <= 0) size = 4096;
return new InflaterInputStream(zfin, getInflater(), (int)size) {
private boolean isClosed = false;
public void close() throws IOException {
if (!isClosed) {
releaseInflater(inf);
this.in.close();
isClosed = true;
}
}
// Override fill() method to provide an extra "dummy" byte
// at the end of the input stream. This is required when
// using the "nowrap" Inflater option.
protected void fill() throws IOException {
if (eof) {
throw new EOFException(
"Unexpected end of ZLIB input stream");
}
len = this.in.read(buf, 0, buf.length);
if (len == -1) {
buf[0] = 0;
len = 1;
eof = true;
}
inf.setInput(buf, 0, len);
}
private boolean eof;
public int available() throws IOException {
if (isClosed)
return 0;
long avail = zfin.size() - inf.getBytesWritten();
return avail > (long) Integer.MAX_VALUE ?
Integer.MAX_VALUE : (int) avail;
}
};
default:
throw new ZipException("invalid compression method");
}
}
private static native int getMethod(long jzentry);
/*
* Gets an inflater from the list of available inflaters or allocates
* a new one.
*/
private Inflater getInflater() {
synchronized (inflaters) {
int size = inflaters.size();
if (size > 0) {
Inflater inf = (Inflater)inflaters.remove(size - 1);
return inf;
} else {
return new Inflater(true);
}
}
}
/*
* Releases the specified inflater to the list of available inflaters.
*/
private void releaseInflater(Inflater inf) {
synchronized (inflaters) {
inf.reset();
inflaters.add(inf);
}
}
// List of available Inflater objects for decompression
private Vector inflaters = new Vector();
/**
* Returns the path name of the ZIP file.
* @return the path name of the ZIP file
*/
public String getName() {
return name;
}
/**
* Returns an enumeration of the ZIP file entries.
* @return an enumeration of the ZIP file entries
* @throws IllegalStateException if the zip file has been closed
*/
public Enumeration<? extends ZipEntry> entries() {
ensureOpen();
return new Enumeration<ZipEntry>() {
private int i = 0;
public boolean hasMoreElements() {
synchronized (ZipFile.this) {
ensureOpen();
return i < total;
}
}
public ZipEntry nextElement() throws NoSuchElementException {
synchronized (ZipFile.this) {
ensureOpen();
if (i >= total) {
throw new NoSuchElementException();
}
long jzentry = getNextEntry(jzfile, i++);
if (jzentry == 0) {
String message;
if (closeRequested) {
message = "ZipFile concurrently closed";
} else {
message = getZipMessage(ZipFile.this.jzfile);
}
throw new ZipError("jzentry == 0" +
",\n jzfile = " + ZipFile.this.jzfile +
",\n total = " + ZipFile.this.total +
",\n name = " + ZipFile.this.name +
",\n i = " + i +
",\n message = " + message
);
}
ZipEntry ze = new ZipEntry(jzentry);
freeEntry(jzfile, jzentry);
return ze;
}
}
};
}
private static native long getNextEntry(long jzfile, int i);
/**
* Returns the number of entries in the ZIP file.
* @return the number of entries in the ZIP file
* @throws IllegalStateException if the zip file has been closed
*/
public int size() {
ensureOpen();
return total;
}
/**
* Closes the ZIP file.
* <p> Closing this ZIP file will close all of the input streams
* previously returned by invocations of the {@link #getInputStream
* getInputStream} method.
*
* @throws IOException if an I/O error has occurred
*/
public void close() throws IOException {
synchronized (this) {
closeRequested = true;
if (jzfile != 0) {
// Close the zip file
long zf = this.jzfile;
jzfile = 0;
close(zf);
// Release inflaters
synchronized (inflaters) {
int size = inflaters.size();
for (int i = 0; i < size; i++) {
Inflater inf = (Inflater)inflaters.get(i);
inf.end();
}
}
}
}
}
/**
* Ensures that the <code>close</code> method of this ZIP file is
* called when there are no more references to it.
*
* <p>
* Since the time when GC would invoke this method is undetermined,
* it is strongly recommended that applications invoke the <code>close</code>
* method as soon they have finished accessing this <code>ZipFile</code>.
* This will prevent holding up system resources for an undetermined
* length of time.
*
* @throws IOException if an I/O error has occurred
* @see java.util.zip.ZipFile#close()
*/
protected void finalize() throws IOException {
close();
}
private static native void close(long jzfile);
private void ensureOpen() {
if (closeRequested) {
throw new IllegalStateException("zip file closed");
}
if (jzfile == 0) {
throw new IllegalStateException("The object is not initialized.");
}
}
private void ensureOpenOrZipException() throws IOException {
if (closeRequested) {
throw new ZipException("ZipFile closed");
}
}
/*
* Inner class implementing the input stream used to read a
* (possibly compressed) zip file entry.
*/
private class ZipFileInputStream extends InputStream {
protected long jzentry; // address of jzentry data
private long pos; // current position within entry data
protected long rem; // number of remaining bytes within entry
protected long size; // uncompressed size of this entry
ZipFileInputStream(long jzentry) {
pos = 0;
rem = getCSize(jzentry);
size = getSize(jzentry);
this.jzentry = jzentry;
}
public int read(byte b[], int off, int len) throws IOException {
if (rem == 0) {
return -1;
}
if (len <= 0) {
return 0;
}
if (len > rem) {
len = (int) rem;
}
synchronized (ZipFile.this) {
ensureOpenOrZipException();
len = ZipFile.read(ZipFile.this.jzfile, jzentry, pos, b,
off, len);
}
if (len > 0) {
pos += len;
rem -= len;
}
if (rem == 0) {
close();
}
return len;
}
public int read() throws IOException {
byte[] b = new byte[1];
if (read(b, 0, 1) == 1) {
return b[0] & 0xff;
} else {
return -1;
}
}
public long skip(long n) {
if (n > rem)
n = rem;
pos += n;
rem -= n;
if (rem == 0) {
close();
}
return n;
}
public int available() {
return rem > Integer.MAX_VALUE ? Integer.MAX_VALUE : (int) rem;
}
public long size() {
return size;
}
public void close() {
rem = 0;
synchronized (ZipFile.this) {
if (jzentry != 0 && ZipFile.this.jzfile != 0) {
freeEntry(ZipFile.this.jzfile, jzentry);
jzentry = 0;
}
}
}
}
private static native int read(long jzfile, long jzentry,
long pos, byte[] b, int off, int len);
private static native long getCSize(long jzentry);
private static native long getSize(long jzentry);
// Temporary add on for bug troubleshooting
private static native String getZipMessage(long jzfile);
}