src.gov.nasa.worldwind.ogc.kml.io.KMZInputStream Maven / Gradle / Ivy
/*
* Copyright (C) 2012 United States Government as represented by the Administrator of the
* National Aeronautics and Space Administration.
* All Rights Reserved.
*/
package gov.nasa.worldwind.ogc.kml.io;
import gov.nasa.worldwind.util.*;
import java.io.*;
import java.util.*;
import java.util.zip.*;
/**
* Implements the {@link KMLDoc} interface for KMZ files read from a stream.
*
* @author tag
* @version $Id: KMZInputStream.java 1171 2013-02-11 21:45:02Z dcollins $
*/
public class KMZInputStream implements KMLDoc
{
/** The zip stream created for the specified input stream. */
protected ZipInputStream zipStream;
/**
* The next entry to read from the input stream. This field refers to the first entry in the stream when the
* constructor returns, and after each entry is copied to the temp dir it is updated to point to the subsequent
* entry. If null, the stream contains no more entries.
*/
protected ZipEntry currentEntry;
/** A mapping of the files in the KMZ stream to their location in the temporary directory. */
protected Map files;
/** The directory to hold files copied from the stream. Both the directory and the files copied there are temporary. */
protected File tempDir;
/**
* Constructs a KMZInputStream instance. Upon return, the new instance's current-entry field refers to the first
* entry in the stream.
*
* @param sourceStream the input stream to read from.
*
* @throws IllegalArgumentException if the specified stream is null.
* @throws java.io.IOException if an error occurs while accessing the stream.
*/
public KMZInputStream(InputStream sourceStream) throws IOException
{
if (sourceStream == null)
{
String message = Logging.getMessage("nullValue.InputStreamIsNull");
Logging.logger().severe(message);
throw new IllegalArgumentException(message);
}
this.zipStream = new ZipInputStream(sourceStream);
this.files = new HashMap();
this.moveToNextEntry();
}
/**
* Moves this stream to its next zip entry and updates this stream's current-entry field.
*
* @throws IOException if an exception occurs while attempting to more the stream to the next entry.
*/
protected void moveToNextEntry() throws IOException
{
ZipEntry nextEntry = this.zipStream.getNextEntry();
// Close the stream if there's nothing more to read from it.
if (nextEntry == null && this.currentEntry != null)
this.zipStream.close();
this.currentEntry = nextEntry;
}
/**
* Returns an {@link java.io.InputStream} to the first KML file within the stream.
*
* @return an input stream positioned to the first KML file in the stream, or null if the stream does not contain a
* KML file.
*
* @throws IOException if an error occurs while reading the stream.
*/
public synchronized InputStream getKMLStream() throws IOException
{
// Iterate through the stream's entries to find the KML file. It will normally be the first entry, but there's
// no guarantee of that. If another file is encountered before the KML file, copy it to temp dir created to
// capture the KMZ document's directory hierarchy.
while (this.currentEntry != null)
{
if (this.currentEntry.getName().toLowerCase().endsWith(".kml"))
{
String kmlEntryName = this.currentEntry.getName();
this.copyCurrentEntryToTempDir(); // copies the current entry to a temp file and adds it to this.files
File file = this.files.get(kmlEntryName);
return file != null ? new FileInputStream(file) : null;
}
else
{
this.copyCurrentEntryToTempDir();
}
}
return null;
}
/**
* Returns an {@link InputStream} to a specified file within the KMZ stream. The file's path is resolved relative to
* the internal root of the KMZ file represented by the stream.
*
* Note: Since relative references to files outside the stream have no meaning, this class does not resolve relative
* references to files in other KMZ archives. For example, it does not resolve references like this:
* ../other.kmz/file.png.
*
* @param path the path of the requested file.
*
* @return an input stream positioned to the start of the requested file, or null if the file does not exist or the
* specified path is absolute.
*
* @throws IllegalArgumentException if the path is null.
* @throws IOException if an error occurs while attempting to read the input stream.
*/
public synchronized InputStream getSupportFileStream(String path) throws IOException
{
// This method is called by the native WebView implementation to resolve resources in KMZ balloons. It may
// not perform any synchronization with the EDT (such as calling invokeAndWait), or it will introduce a
// potential deadlock when called by the WebView's native UI thread.
if (path == null)
{
String message = Logging.getMessage("nullValue.FilePathIsNull");
Logging.logger().severe(message);
throw new IllegalArgumentException(message);
}
// Regardless of whether the next entry in the stream is the requested file, copy each entry encountered to
// the temporary directory created to represent the directory hierarchy in the KMZ document. If the most
// recently copied file is the requested file, return it and suspend reading and copying until it's again
// necessary. This prevents bogging down performance until everything is copied.
File file = files.get(path);
if (file != null)
return new FileInputStream(file);
if (this.currentEntry == null) // no more entries in the zip stream
return null;
this.copyCurrentEntryToTempDir();
// If the file just copied is the one requested, a recursive call will pick it up immediately.
return this.getSupportFileStream(path);
}
/**
* Returns an absolute path to a specified file within the KMZ stream. The file's path is resolved relative to the
* internal root of the KMZ file represented by the stream.
*
* Note: Since relative references to files outside the stream have no meaning, this class does not resolve relative
* references to files in other KMZ archives. For example, it does not resolve references like this:
* ../other.kmz/file.png.
*
* @param path the path of the requested file.
*
* @return an absolute path for the requested file, or null if the file does not exist or the specified path is
* absolute.
*
* @throws IllegalArgumentException if the path is null.
* @throws IOException if an error occurs while attempting to create a temporary file.
*/
public synchronized String getSupportFilePath(String path) throws IOException
{
// This method is called by the native WebView implementation to resolve resources in KMZ balloons. It may
// not perform any synchronization with the EDT (such as calling invokeAndWait), or it will introduce a
// potential deadlock when called by the WebView's native UI thread.
if (path == null)
{
String message = Logging.getMessage("nullValue.FilePathIsNull");
Logging.logger().severe(message);
throw new IllegalArgumentException(message);
}
// Regardless of whether the next entry in the stream is the requested file, copy each entry encountered to
// the temporary directory created to represent the directory hierarchy in the KMZ document. If the most
// recently copied file is the requested file, return it and suspend reading and copying until it's again
// necessary. This prevents bogging down performance until everything is copied.
File file = files.get(path);
if (file != null)
return file.getPath();
if (this.currentEntry == null) // no more entries in the zip stream
return null;
this.copyCurrentEntryToTempDir();
// If the file just copied is the one requested, a recursive call will pick it up immediately. If not, the next
// entry will be retrieved.
return this.getSupportFilePath(path);
}
/**
* Copies a file from the input stream to the temporary area created to represent the KMZ contents. If that area
* does not yet exists, it is created.
*
* Note: This method should be called only by another synchronized method of this instance.
*
* @throws IOException if an error occurs during the copy.
*/
protected void copyCurrentEntryToTempDir() throws IOException
{
if (this.currentEntry == null) // no more entries in the zip stream
return;
if (this.currentEntry.isDirectory())
{
this.moveToNextEntry();
return;
}
if (this.tempDir == null)
this.tempDir = WWIO.makeTempDir();
if (this.tempDir == null) // unlikely to occur, but define a reaction
{
String message = Logging.getMessage("generic.UnableToCreateTempDir", this.tempDir);
Logging.logger().warning(message);
return;
}
// Create the path for the temp file and ensure all directories leading to it exist.
String tempFileName = this.tempDir + File.separator + this.currentEntry.getName();
WWIO.makeParentDirs(tempFileName);
// Copy the entry.
File outFile = new File(tempFileName);
outFile.deleteOnExit();
WWIO.saveBuffer(WWIO.readStreamToBuffer(this.zipStream), outFile);
this.files.put(this.currentEntry.getName(), outFile);
// Increment the stream to the next entry.
this.moveToNextEntry();
}
//
// public static void main(String[] args)
// {
// try
// {
// InputStream is = new FileInputStream(new File("/Users/tag/NoBackup/kml/ocean_model_locations.kmz"));
// KMZInputStream zStream = new KMZInputStream(is);
// InputStream kmlStream = zStream.getKMLStream();
// is = zStream.getSupportFileStream("files/camera_mode.png");
// is = zStream.getSupportFileStream("files/3DBuildingsLayer3.png");
// is = zStream.getSupportFileStream("files/camera_mode.png");
// if (kmlStream != null)
// {
// KMLRoot root = KMLRoot.create(kmlStream);
// root.parse();
// }
// }
// catch (IOException e)
// {
// e.printStackTrace();
// }
// catch (XMLStreamException e)
// {
// e.printStackTrace();
// }
// }
}