Java tutorial
//package com.java2s; /* * Copyright 2006-2015 WebPKI.org (http://webpki.org). * * 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 java.io.IOException; import java.io.InputStream; import java.io.File; import java.io.FileInputStream; import java.io.ByteArrayOutputStream; public class Main { public static byte[] readFile(File file) throws IOException { return getByteArrayFromInputStream(new FileInputStream(file)); } public static byte[] readFile(String filename) throws IOException { return readFile(new File(filename)); } public static byte[] getByteArrayFromInputStream(InputStream is) throws IOException { ByteArrayOutputStream baos = new ByteArrayOutputStream(10000); byte[] buffer = new byte[10000]; int bytes; while ((bytes = is.read(buffer)) != -1) { baos.write(buffer, 0, bytes); } is.close(); return baos.toByteArray(); } }