content: /*
   * Licensed to the Apache Software Foundation (ASF) under one
   * or more contributor license agreements.  See the NOTICE file
   * distributed with this work for additional information
   * regarding copyright ownership.  The ASF licenses this file
   * to you 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 org.apache.chemistry.opencmis.inmemory.storedobj.impl;
  
  import java.io.IOException;
  import java.io.InputStream;
  import java.util.Random;
  
  public class RandomInputStream extends InputStream {
  
      private Random random = new Random();
      private boolean isClosed = false;
      private long size;
      private long bytesRead;
  
      public RandomInputStream(long size) {
          this.size = size;
      }
      
      @Override
      public int read() throws IOException {
          checkOpen();
          long len = checkLimit(1);
          if (len > 0) {
              int result = random.nextInt() % 256;
              if (result < 0) {
                  result = -result;
              }
              bytesRead++;
              return result;
          } else {
              return -1;
          }
      }
  
      @Override
      public int read(byte[] data, int offset, int length) throws IOException {
          checkOpen();
          int sizeToRead = (int)checkLimit(length);
          if (0 == sizeToRead) {
              return -1;
          }
  
          byte[] temp = new byte[sizeToRead];
          random.nextBytes(temp);
          System.arraycopy(temp, 0, data, offset, sizeToRead);
          bytesRead += length;
          return length;
      }
  
      @Override
      public int read(byte[] data) throws IOException {
          checkOpen();
          long len = checkLimit(data.length);
          if (0 == len) {
              return -1;
          }
          random.nextBytes(data);
          bytesRead += len;
          return (int) len;
      }
  
      @Override
      public long skip(long bytesToSkip) throws IOException {
          checkOpen();
          long skip = checkLimit(bytesToSkip);
          bytesRead += skip;
          return skip;
      }
  
      @Override
      public void close() {
          this.isClosed = true;
      }
  
      @Override
      public int available() {
          return (int)(size - bytesRead);
      }
  
      private void checkOpen() throws IOException {
          if (isClosed) {
              throw new IOException("RandomInputStream was already closed.");
          }
      }
  
      private long checkLimit(long sizeRequested) {
          if (bytesRead >= size) {
              return 0;
          } else if (bytesRead + sizeRequested >= size) {
              return size - bytesRead;
          } else {
              return sizeRequested;
          }
      }
  
  }
  