com.manning.androidhacks.hack040.util.Utils.java Source code

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Here is the source code for com.manning.androidhacks.hack040.util.Utils.java

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/*
50AH-code
=========
    
50 Android Hacks (http://manning.com/sessa/) book source code
    
    
Copyright (c) 2012 Manning
    
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
    
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
    
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
    
    
*/

/*
 * Copyright (C) 2012 The Android Open Source Project
 *
 * 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.manning.androidhacks.hack040.util;

import android.annotation.SuppressLint;
import android.app.ActivityManager;
import android.content.Context;
import android.graphics.Bitmap;
import android.os.Build;
import android.os.Environment;
import android.os.StatFs;

import java.io.File;

/**
 * Class containing some static utility methods.
 */
public class Utils {
    public static final int IO_BUFFER_SIZE = 8 * 1024;

    private Utils() {
    };

    /**
     * Workaround for bug pre-Froyo, see here for more info:
     * http://android-developers.blogspot.com/2011/09/androids-http-clients.html
     */
    public static void disableConnectionReuseIfNecessary() {
        // HTTP connection reuse which was buggy pre-froyo
        if (hasHttpConnectionBug()) {
            System.setProperty("http.keepAlive", "false");
        }
    }

    /**
     * Get the size in bytes of a bitmap.
     * 
     * @param bitmap
     * @return size in bytes
     */
    @SuppressLint("NewApi")
    public static int getBitmapSize(Bitmap bitmap) {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB_MR1) {
            return bitmap.getByteCount();
        }
        // Pre HC-MR1
        return bitmap.getRowBytes() * bitmap.getHeight();
    }

    /**
     * Check if external storage is built-in or removable.
     * 
     * @return True if external storage is removable (like an SD card), false
     *         otherwise.
     */
    @SuppressLint("NewApi")
    public static boolean isExternalStorageRemovable() {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.GINGERBREAD) {
            return Environment.isExternalStorageRemovable();
        }
        return true;
    }

    /**
     * Get the external app cache directory.
     * 
     * @param context
     *          The context to use
     * @return The external cache dir
     */
    @SuppressLint("NewApi")
    public static File getExternalCacheDir(Context context) {
        if (hasExternalCacheDir()) {
            return context.getExternalCacheDir();
        }

        // Before Froyo we need to construct the external cache dir ourselves
        final String cacheDir = "/Android/data/" + context.getPackageName() + "/cache/";
        return new File(Environment.getExternalStorageDirectory().getPath() + cacheDir);
    }

    /**
     * Check how much usable space is available at a given path.
     * 
     * @param path
     *          The path to check
     * @return The space available in bytes
     */
    @SuppressLint("NewApi")
    public static long getUsableSpace(File path) {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.GINGERBREAD) {
            return path.getUsableSpace();
        }
        final StatFs stats = new StatFs(path.getPath());
        return (long) stats.getBlockSize() * (long) stats.getAvailableBlocks();
    }

    /**
     * Get the memory class of this device (approx. per-app memory limit)
     * 
     * @param context
     * @return
     */
    public static int getMemoryClass(Context context) {
        return ((ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE)).getMemoryClass();
    }

    /**
     * Check if OS version has a http URLConnection bug. See here for more
     * information:
     * http://android-developers.blogspot.com/2011/09/androids-http-clients.html
     * 
     * @return
     */
    public static boolean hasHttpConnectionBug() {
        return Build.VERSION.SDK_INT < Build.VERSION_CODES.FROYO;
    }

    /**
     * Check if OS version has built-in external cache dir method.
     * 
     * @return
     */
    public static boolean hasExternalCacheDir() {
        return Build.VERSION.SDK_INT >= Build.VERSION_CODES.FROYO;
    }

    /**
     * Check if ActionBar is available.
     * 
     * @return
     */
    public static boolean hasActionBar() {
        return Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB;
    }
}