content: /*
   * Copyright (C) 2007 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.taobao.android.dex.util;
  
  import java.io.File;
  import java.io.FileInputStream;
  import java.io.IOException;
  
  /**
   * File I/O utilities.
   */
  public final class FileUtils {
      private FileUtils() {
      }
  
      /**
       * Reads the named file, translating {@link IOException} to a
       * {@link RuntimeException} of some sort.
       *
       * @param fileName {@code non-null;} name of the file to read
       * @return {@code non-null;} contents of the file
       */
      public static byte[] readFile(String fileName) {
          File file = new File(fileName);
          return readFile(file);
      }
  
      /**
       * Reads the given file, translating {@link IOException} to a
       * {@link RuntimeException} of some sort.
       *
       * @param file {@code non-null;} the file to read
       * @return {@code non-null;} contents of the file
       */
      public static byte[] readFile(File file) {
          if (!file.exists()) {
              throw new RuntimeException(file + ": file not found");
          }
  
          if (!file.isFile()) {
              throw new RuntimeException(file + ": not a file");
          }
  
          if (!file.canRead()) {
              throw new RuntimeException(file + ": file not readable");
          }
  
          long longLength = file.length();
          int length = (int) longLength;
          if (length != longLength) {
              throw new RuntimeException(file + ": file too long");
          }
  
          byte[] result = new byte[length];
  
          try {
              FileInputStream in = new FileInputStream(file);
              int at = 0;
              while (length > 0) {
                  int amt = in.read(result, at, length);
                  if (amt == -1) {
                      throw new RuntimeException(file + ": unexpected EOF");
                  }
                  at += amt;
                  length -= amt;
              }
              in.close();
          } catch (IOException ex) {
              throw new RuntimeException(file + ": trouble reading", ex);
          }
  
          return result;
      }
  
      /**
       * Returns true if {@code fileName} names a .zip, .jar, or .apk.
       */
      public static boolean hasArchiveSuffix(String fileName) {
          return fileName.endsWith(".zip")
                  || fileName.endsWith(".jar")
                  || fileName.endsWith(".apk");
      }
  }
  