Android example source code file (Formatter.java)

This example Android source code file (Formatter.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, content, formatter, string, stringbuffer

The Formatter.java Android example source code

/*
 * Copyright (C) 2006 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 android.text.format;

import android.content.Context;

/**
 * Utility class to aid in formatting common values that are not covered
 * by the standard java.util.Formatter.
 */
public final class Formatter {

    /**
     * Formats a content size to be in the form of bytes, kilobytes, megabytes, etc
     * 
     * @param context Context to use to load the localized units
     * @param number size value to be formated
     * @return formated string with the number
     */
    public static String formatFileSize(Context context, long number) {
        return formatFileSize(context, number, false);
    }
    
    /**
     * Like {@link #formatFileSize}, but trying to generate shorter numbers
     * (showing fewer digits of precisin).
     */
    public static String formatShortFileSize(Context context, long number) {
        return formatFileSize(context, number, true);
    }
    
    private static String formatFileSize(Context context, long number, boolean shorter) {
        if (context == null) {
            return "";
        }

        float result = number;
        int suffix = com.android.internal.R.string.byteShort;
        if (result > 900) {
            suffix = com.android.internal.R.string.kilobyteShort;
            result = result / 1024;
        }
        if (result > 900) {
            suffix = com.android.internal.R.string.megabyteShort;
            result = result / 1024;
        }
        if (result > 900) {
            suffix = com.android.internal.R.string.gigabyteShort;
            result = result / 1024;
        }
        if (result > 900) {
            suffix = com.android.internal.R.string.terabyteShort;
            result = result / 1024;
        }
        if (result > 900) {
            suffix = com.android.internal.R.string.petabyteShort;
            result = result / 1024;
        }
        String value;
        if (result < 1) {
            value = String.format("%.2f", result);
        } else if (result < 10) {
            if (shorter) {
                value = String.format("%.1f", result);
            } else {
                value = String.format("%.2f", result);
            }
        } else if (result < 100) {
            if (shorter) {
                value = String.format("%.0f", result);
            } else {
                value = String.format("%.2f", result);
            }
        } else {
            value = String.format("%.0f", result);
        }
        return context.getResources().
            getString(com.android.internal.R.string.fileSizeSuffix,
                      value, context.getString(suffix));
    }
    
    /**
     * Returns a string in the canonical IP format ###.###.###.### from a packed integer containing
     * the IP address.  The IP address is expected to be in little-endian format (LSB first). That
     * is, 0x01020304 will return "4.3.2.1".
     * 
     * @param addr the IP address as a packed integer with LSB first.
     * @return string with canonical IP address format.
     */
    public static String formatIpAddress(int addr) {
        StringBuffer buf = new StringBuffer();
        buf.append(addr  & 0xff).append('.').
            append((addr >>>= 8) & 0xff).append('.').
            append((addr >>>= 8) & 0xff).append('.').
            append((addr >>>= 8) & 0xff);
        return buf.toString();
    }
}