hadoop-ozone/integration-test/src/test/java/org/apache/hadoop/ozone/StandardOutputTestBase.java

/*
 * 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.hadoop.ozone;

import org.junit.After;
import org.junit.Before;

import java.io.ByteArrayOutputStream;
import java.io.PrintStream;
import java.io.UnsupportedEncodingException;
import java.nio.charset.StandardCharsets;

/**
 * Utility class to check standard output.
 */
public class StandardOutputTestBase {
  private final ByteArrayOutputStream outContent =
      new ByteArrayOutputStream();
  private final ByteArrayOutputStream errContent =
      new ByteArrayOutputStream();
  private final PrintStream originalOut = System.out;
  private final PrintStream originalErr = System.err;
  private static final String DEFAULT_ENCODING = StandardCharsets.UTF_8.name();

  /**
   * Set up fresh output and error streams before test.
   *
   * @throws UnsupportedEncodingException
   */
  @Before
  public void setUpStreams() throws UnsupportedEncodingException {
    System.setOut(new PrintStream(outContent, false, DEFAULT_ENCODING));
    System.setErr(new PrintStream(errContent, false, DEFAULT_ENCODING));
  }

  /**
   * Restore original error and output streams after test.
   */
  @After
  public void restoreStreams() {
    System.setOut(originalOut);
    System.setErr(originalErr);
  }

  public String getOutContentString()
      throws UnsupportedEncodingException {
    return getOutContentString(DEFAULT_ENCODING);
  }

  public String getErrContentString()
      throws UnsupportedEncodingException {
    return getErrContentString(DEFAULT_ENCODING);
  }

  public String getOutContentString(String encoding)
      throws UnsupportedEncodingException {
    return outContent.toString(encoding);
  }

  public String getErrContentString(String encoding)
      throws UnsupportedEncodingException {
    return errContent.toString(encoding);
  }

  public String getDefaultEncoding() {
    return DEFAULT_ENCODING;
  }

}