/*
* This file is part of the Echo Web Application Framework (hereinafter "Echo").
* Copyright (C) 2002-2009 NextApp, Inc.
*
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*/
package nextapp.echo2.app;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
/**
* A representation of an image that will be retrieved as a resource from
* the CLASSPATH.
*/
public class ResourceImageReference
extends StreamImageReference {
/**
* Size of buffer used for reading image data from CLASSPATH and writing
* it to <code>OutputStream</code>s.
*/
private static final int BUFFER_SIZE = 4096;
/**
* Mapping of extensions to content types.
*/
private static final Map extensionToContentType;
static {
Map map = new HashMap();
map.put("gif", "image/gif");
map.put("png", "image/png");
map.put("jpeg", "image/jpeg");
map.put("jpg", "image/jpg");
map.put("bmp", "image/bmp");
extensionToContentType = Collections.unmodifiableMap(map);
}
/**
* Automatically determines the content type based on the name of a
* resource.
*
* @param resourceName the resource name
* @return the discovered content type
* @throws IllegalArgumentException if no content type can be determined
*/
private static final String getContentType(String resourceName) {
String contentType;
// Determine content type.
int extensionDelimiterPosition = resourceName.lastIndexOf(".");
if (extensionDelimiterPosition == -1) {
throw new IllegalArgumentException("Invalid file extension (resource has no extension: " + resourceName + ")");
} else {
String extension = resourceName.substring(extensionDelimiterPosition + 1).toLowerCase();
contentType = (String) extensionToContentType.get(extension);
if (contentType == null) {
throw new IllegalArgumentException("Invalid file extension (no matching content type: " + resourceName + ")");
}
}
return contentType;
}
private Extent width, height;
private String contentType;
private String resource;
private String id;
/**
* Creates a <code>ResourceImageReference</code>.
* The content type will be automatically determined.
*
* @param resource the resource name containing the binary image data
*/
public ResourceImageReference(String resource) {
this(resource, null, null, null);
}
/**
* Creates a <code>ResourceImageReference</code>.
*
* @param resource the resource name containing the binary image data
* (all resource names will be treated as absolute, it is
* unnecessary to prepend a leading slash to the resource name)
* @param contentType the content type of the image (or null to
* automatically determine the content type based on the resource
* extension)
*/
public ResourceImageReference(String resource, String contentType) {
this(resource, contentType, null, null);
}
/**
* Creates a <code>ResourceImageReference</code>.
* The content type will be automatically determined.
*
* @param resource the resource name containing the binary image data
* (all resource names will be treated as absolute, it is
* unnecessary to prepend a leading slash to the resource name)
* @param width the width of the image
* @param height the height of the image
*/
public ResourceImageReference(String resource, Extent width, Extent height) {
this(resource, null, width, height);
}
/**
* Creates a <code>ResourceImageReference</code>.
*
* @param resource the resource name containing the binary image data
* (all resource names will be treated as absolute, it is
* unnecessary to prepend a leading slash to the resource name)
* @param contentType the content type of the image (or null to
* automatically determine the content type based on the resource
* extension)
* @param width the width of the image
* @param height the height of the image
*/
public ResourceImageReference(String resource, String contentType, Extent width, Extent height) {
super();
// Drop leading slash as all resource paths are absolute.
if (resource.charAt(0) == '/') {
this.resource = resource.substring(1);
} else {
this.resource = resource;
}
this.contentType = contentType == null ? getContentType(resource) : contentType;
this.width = width;
this.height = height;
id = ApplicationInstance.generateSystemId();
}
/**
* @see java.lang.Object#equals(java.lang.Object)
*/
public boolean equals(Object o) {
if (!(o instanceof ResourceImageReference)) {
return false;
}
ResourceImageReference that = (ResourceImageReference) o;
if (!(this.resource == that.resource || (this.resource != null && this.resource.equals(that.resource)))) {
return false;
}
if (!(this.contentType == that.contentType || (this.contentType != null && this.contentType.equals(that.contentType)))) {
return false;
}
if (!(this.width == that.width || (this.width != null && this.width.equals(that.width)))) {
return false;
}
if (!(this.height == that.height || (this.height != null && this.height.equals(that.height)))) {
return false;
}
return true;
}
/**
* @see nextapp.echo2.app.StreamImageReference#getContentType()
*/
public String getContentType() {
return contentType;
}
/**
* @see nextapp.echo2.app.ImageReference#getHeight()
*/
public Extent getHeight() {
return height;
}
/**
* @see nextapp.echo2.app.RenderIdSupport#getRenderId()
*/
public String getRenderId() {
return id;
}
/**
* Returns the name of the resource.
*
* @return the name of the resource
*/
public String getResource() {
return resource;
}
/**
* @see nextapp.echo2.app.ImageReference#getWidth()
*/
public Extent getWidth() {
return width;
}
/**
* @see java.lang.Object#hashCode()
*/
public int hashCode() {
return resource == null ? 0 : resource.hashCode();
}
/**
* @see nextapp.echo2.app.StreamImageReference#render(java.io.OutputStream)
*/
public void render(OutputStream out)
throws IOException {
InputStream in = null;
byte[] buffer = new byte[BUFFER_SIZE];
int bytesRead = 0;
try {
in = Thread.currentThread().getContextClassLoader().getResourceAsStream(resource);
if (in == null) {
throw new IllegalArgumentException("Specified resource does not exist: " + resource + ".");
}
do {
bytesRead = in.read(buffer);
if (bytesRead > 0) {
out.write(buffer, 0, bytesRead);
}
} while (bytesRead > 0);
} finally {
if (in != null) { try { in.close(); } catch (IOException ex) { } }
}
}
}