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.causeway.core.metamodel.commons;
  
  import java.io.ByteArrayInputStream;
  import java.io.ByteArrayOutputStream;
  
  import org.hamcrest.Description;
  import org.hamcrest.Matcher;
  import org.hamcrest.TypeSafeMatcher;
  import org.junit.jupiter.api.AfterEach;
  import org.junit.jupiter.api.BeforeEach;
  import org.junit.jupiter.api.Test;
  
  import static org.hamcrest.MatcherAssert.assertThat;
  import static org.junit.jupiter.api.Assertions.assertThrows;
  
  public class IoUtils_CopyTest {
  
      private static final class ArrayMatcher extends TypeSafeMatcher<byte[]> {
  
          private final byte[] expectedBytes;
  
          public ArrayMatcher(final byte[] expectedBytes) {
              this.expectedBytes = expectedBytes;
          }
  
          @Override
          public boolean matchesSafely(final byte[] actualBytes) {
              if (actualBytes.length != expectedBytes.length) {
                  return false;
              }
              for (int i = 0; i < actualBytes.length; i++) {
                  if (actualBytes[i] != expectedBytes[i]) {
                      return false;
                  }
              }
              return true;
          }
  
          @Override
          public void describeTo(final Description arg0) {
              arg0.appendText("does not match expected array");
          }
      }
  
      private static int BUF_INTERNAL_SIZE = 1024;
  
      @BeforeEach
      public void setUp() throws Exception {
      }
  
      @AfterEach
      public void tearDown() throws Exception {
      }
  
      @Test
      public void handlesNullInputStream() throws Exception {
          final ByteArrayInputStream bais = null;
          final ByteArrayOutputStream baos = new ByteArrayOutputStream();
          assertThrows(IllegalArgumentException.class, ()->
              InputStreamExtensions.copyTo(bais, baos));
      }
  
      @Test
      public void handlesNullOutputStream() throws Exception {
          final byte[] bytes = createByteArray(10);
          final ByteArrayInputStream bais = new ByteArrayInputStream(bytes);
          final ByteArrayOutputStream baos = null;
          assertThrows(IllegalArgumentException.class, ()->
              InputStreamExtensions.copyTo(bais, baos));
      }
  
      @Test
      public void copiesEmptyInputStream() throws Exception {
          final byte[] bytes = createByteArray(0);
          final ByteArrayInputStream bais = new ByteArrayInputStream(bytes);
          final ByteArrayOutputStream baos = new ByteArrayOutputStream();
          InputStreamExtensions.copyTo(bais, baos);
          assertThat(baos.toByteArray(), arrayEqualTo(bytes));
      }
  
      @Test
      public void copiesInputStreamSmallerThanInternalBuffer() throws Exception {
          final byte[] bytes = createByteArray(BUF_INTERNAL_SIZE - 1);
          final ByteArrayInputStream bais = new ByteArrayInputStream(bytes);
          final ByteArrayOutputStream baos = new ByteArrayOutputStream();
          InputStreamExtensions.copyTo(bais, baos);
          assertThat(baos.toByteArray(), arrayEqualTo(bytes));
      }
  
      @Test
      public void copiesInputStreamLargerThanInternalBuffer() throws Exception {
          final byte[] bytes = createByteArray(BUF_INTERNAL_SIZE + 1);
          final ByteArrayInputStream bais = new ByteArrayInputStream(bytes);
          final ByteArrayOutputStream baos = new ByteArrayOutputStream();
          InputStreamExtensions.copyTo(bais, baos);
          assertThat(baos.toByteArray(), arrayEqualTo(bytes));
      }
  
      @Test
      public void copiesInputStreamExactlySameSizeAsInternalBuffer() throws Exception {
          final byte[] bytes = createByteArray(BUF_INTERNAL_SIZE);
          final ByteArrayInputStream bais = new ByteArrayInputStream(bytes);
          final ByteArrayOutputStream baos = new ByteArrayOutputStream();
          InputStreamExtensions.copyTo(bais, baos);
          assertThat(baos.toByteArray(), arrayEqualTo(bytes));
      }
  
      private Matcher<byte[]> arrayEqualTo(final byte[] bytes) {
          return new ArrayMatcher(bytes);
      }
  
      private byte[] createByteArray(final int size) {
          final byte[] bytes = new byte[size];
          for (int i = 0; i < size; i++) {
              bytes[i] = (byte) i;
          }
          return bytes;
      }
  
  }
  