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Contains common I/O, date parsing, and XML processing classes.
/*
* #%L
* Common package for I/O and related utilities
* %%
* Copyright (C) 2005 - 2016 Open Microscopy Environment:
* - Board of Regents of the University of Wisconsin-Madison
* - Glencoe Software, Inc.
* - University of Dundee
* %%
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
* #L%
*/
package loci.common;
import java.io.BufferedInputStream;
import java.io.DataInputStream;
import java.io.File;
import java.io.IOException;
import java.util.zip.ZipEntry;
import java.util.zip.ZipInputStream;
/**
* StreamHandle implementation for reading from Zip-compressed files
* or byte arrays. Instances of ZipHandle are read-only.
*
* @see StreamHandle
*
* @author Melissa Linkert melissa at glencoesoftware.com
*/
public class ZipHandle extends StreamHandle {
// -- Fields --
private RandomAccessInputStream in;
private ZipInputStream zip;
private String entryName;
private int entryCount;
// -- Constructor --
public ZipHandle(String file) throws IOException {
super();
this.file = file;
in = openStream(file);
zip = new ZipInputStream(in);
entryName = null;
entryCount = 0;
// strip off .zip extension and directory prefix
String innerFile = file.substring(0, file.length() - 4);
int slash = innerFile.lastIndexOf(File.separator);
if (slash < 0) slash = innerFile.lastIndexOf("/");
if (slash >= 0) innerFile = innerFile.substring(slash + 1);
// look for Zip entry with same prefix as the Zip file itself
boolean matchFound = false;
length = 0;
while (true) {
ZipEntry ze = zip.getNextEntry();
if (ze == null) break;
if (entryName == null) entryName = ze.getName();
if (!matchFound && ze.getName().startsWith(innerFile)) {
// found entry with matching name
entryName = ze.getName();
matchFound = true;
}
entryCount++;
length += ze.getSize();
}
resetStream();
if (length <= 0) {
populateLength();
}
}
/**
* Constructs a new ZipHandle corresponding to the given entry of the
* specified Zip file.
*
* @param file a name that can be passed to
* {@link Location#getHandle(String, boolean, boolean)}
* @param entry the specific entry in the Zip file to be opened
* @throws HandleException if the given file is not a Zip file.
* @see ZipEntry
*/
public ZipHandle(String file, ZipEntry entry) throws IOException {
super();
this.file = file;
in = openStream(file);
zip = new ZipInputStream(in);
entryName = entry.getName();
entryCount = 1;
seekToEntry();
resetStream();
length = entry.getSize();
if (length <= 0) {
populateLength();
}
}
// -- ZipHandle API methods --
/**
* @param file a name that can be passed to
* {@link Location#getHandle(String, boolean, boolean)}
* @return true if the given filename is a Zip file.
* @throws IOException if the file cannot be read
*/
public static boolean isZipFile(String file) throws IOException {
if (!file.toLowerCase().endsWith(".zip")) return false;
IRandomAccess handle = getHandle(file);
byte[] b = new byte[2];
if (handle.length() >= 2) {
handle.read(b);
}
handle.close();
return new String(b, Constants.ENCODING).equals("PK");
}
/**
* @return the name of the backing Zip entry.
*/
public String getEntryName() {
return entryName;
}
/**
* @return the DataInputStream corresponding to the backing Zip entry.
*/
public DataInputStream getInputStream() {
return stream;
}
/**
* @return the number of entries.
*/
public int getEntryCount() {
return entryCount;
}
// -- IRandomAccess API methods --
/* @see IRandomAccess#close() */
@Override
public void close() throws IOException {
super.close();
zip = null;
entryName = null;
if (in != null) in.close();
in = null;
entryCount = 0;
}
// -- StreamHandle API methods --
/* @see StreamHandle#resetStream() */
@Override
protected void resetStream() throws IOException {
if (stream != null) stream.close();
if (in != null) {
in.close();
in = openStream(file);
}
if (zip != null) zip.close();
zip = new ZipInputStream(in);
if (entryName != null) seekToEntry();
stream = new DataInputStream(new BufferedInputStream(
zip, RandomAccessInputStream.MAX_OVERHEAD));
stream.mark(RandomAccessInputStream.MAX_OVERHEAD);
}
// -- Helper methods --
private void seekToEntry() throws IOException {
while (!entryName.equals(zip.getNextEntry().getName()));
}
private void populateLength() throws IOException {
length = -1;
while (stream.available() > 0) {
stream.skip(1);
length++;
}
resetStream();
}
private static IRandomAccess getHandle(String file) throws IOException {
return Location.getHandle(file, false, false);
}
private static RandomAccessInputStream openStream(String file)
throws IOException
{
return new RandomAccessInputStream(getHandle(file), file);
}
}