Android example source code file (BitmapUtils.java)

This example Android source code file (BitmapUtils.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Android by Example" ^TM.

Java - Android tags/keywords

android, bitmap, bitmaputils, bufferedinputstream, bufferedoutputstream, bytearrayoutputstream, could, drawing, graphics, io, io_buffer_size, ioexception, paint, panoramio, string, tag, ui

The BitmapUtils.java Android example source code

/*
 * Copyright (C) 2008 Google Inc.
 *
 * Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.google.android.panoramio;

import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.util.Log;

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.ByteArrayOutputStream;
import java.io.Closeable;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.URL;

/**
 *  Utilities for loading a bitmap from a URL
 *
 */
public class BitmapUtils {
    
    private static final String TAG = "Panoramio";
    
    private static final int IO_BUFFER_SIZE = 4 * 1024;
    
    /**
     * Loads a bitmap from the specified url. This can take a while, so it should not
     * be called from the UI thread.
     * 
     * @param url The location of the bitmap asset
     * 
     * @return The bitmap, or null if it could not be loaded
     */
    public static Bitmap loadBitmap(String url) {
        Bitmap bitmap = null;
        InputStream in = null;
        BufferedOutputStream out = null;

        try {
            in = new BufferedInputStream(new URL(url).openStream(), IO_BUFFER_SIZE);

            final ByteArrayOutputStream dataStream = new ByteArrayOutputStream();
            out = new BufferedOutputStream(dataStream, IO_BUFFER_SIZE);
            copy(in, out);
            out.flush();

            final byte[] data = dataStream.toByteArray();
            bitmap = BitmapFactory.decodeByteArray(data, 0, data.length);
        } catch (IOException e) {
            Log.e(TAG, "Could not load Bitmap from: " + url);
        } finally {
            closeStream(in);
            closeStream(out);
        }

        return bitmap;
    }

    /**
     * Closes the specified stream.
     * 
     * @param stream The stream to close.
     */
    private static void closeStream(Closeable stream) {
        if (stream != null) {
            try {
                stream.close();
            } catch (IOException e) {
                android.util.Log.e(TAG, "Could not close stream", e);
            }
        }
    }

    /**
     * Copy the content of the input stream into the output stream, using a
     * temporary byte array buffer whose size is defined by
     * {@link #IO_BUFFER_SIZE}.
     * 
     * @param in The input stream to copy from.
     * @param out The output stream to copy to.
     * @throws IOException If any error occurs during the copy.
     */
    private static void copy(InputStream in, OutputStream out) throws IOException {
        byte[] b = new byte[IO_BUFFER_SIZE];
        int read;
        while ((read = in.read(b)) != -1) {
            out.write(b, 0, read);
        }
    }

}