Java tutorial
//package com.java2s; /* * Copyright (C) 2014 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. */ import android.graphics.Bitmap; import android.graphics.BitmapFactory; import java.io.IOException; import java.io.InputStream; import java.net.HttpURLConnection; import java.net.URL; public class Main { public static final Bitmap fetchAndRescaleBitmap(String uri, int width, int height) throws IOException { URL url = new URL(uri); HttpURLConnection httpConnection = (HttpURLConnection) url.openConnection(); httpConnection.setDoInput(true); httpConnection.connect(); InputStream inputStream = httpConnection.getInputStream(); int scaleFactor = findScaleFactor(width, height, inputStream); httpConnection = (HttpURLConnection) url.openConnection(); httpConnection.setDoInput(true); httpConnection.connect(); inputStream = httpConnection.getInputStream(); Bitmap bitmap = scaleBitmap(scaleFactor, inputStream); return bitmap; } public static final int findScaleFactor(int targetW, int targetH, InputStream is) { // Get the dimensions of the bitmap BitmapFactory.Options bmOptions = new BitmapFactory.Options(); bmOptions.inJustDecodeBounds = true; BitmapFactory.decodeStream(is, null, bmOptions); int actualW = bmOptions.outWidth; int actualH = bmOptions.outHeight; // Determine how much to scale down the image return Math.min(actualW / targetW, actualH / targetH); } public static final Bitmap scaleBitmap(int scaleFactor, InputStream is) { // Get the dimensions of the bitmap BitmapFactory.Options bmOptions = new BitmapFactory.Options(); // Decode the image file into a Bitmap sized to fill the View bmOptions.inJustDecodeBounds = false; bmOptions.inSampleSize = scaleFactor; Bitmap bitmap = BitmapFactory.decodeStream(is, null, bmOptions); return bitmap; } }