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    1   /*
    2    * Licensed to the Apache Software Foundation (ASF) under one or more
    3    * contributor license agreements. See the NOTICE file distributed with
    4    * this work for additional information regarding copyright ownership.
    5    * The ASF licenses this file to You under the Apache license, Version 2.0
    6    * (the "License"); you may not use this file except in compliance with
    7    * the License. You may obtain a copy of the License at
    8    *
    9    *      http://www.apache.org/licenses/LICENSE-2.0
    10   *
    11   * Unless required by applicable law or agreed to in writing, software
    12   * distributed under the License is distributed on an "AS IS" BASIS,
    13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    14   * See the license for the specific language governing permissions and
    15   * limitations under the license.
    16   */
    17  package org.apache.logging.log4j.status;
    18
    19  import java.io.IOException;
    20  import java.io.PrintStream;
    21
    22  import org.apache.logging.log4j.Level;
    23
    24  /**
    25   * StatusListener that writes to the Console.
    26   */
    27  @SuppressWarnings("UseOfSystemOutOrSystemErr")
    28  public class StatusConsoleListener implements StatusListener {
    29
    30      private Level level = Level.FATAL;
    31      private String[] filters;
    32      private final PrintStream stream;
    33
    34      /**
    35       * Creates the StatusConsoleListener using the supplied Level.
    36       * @param level The Level of status messages that should appear on the console.
    37       */
    38      public StatusConsoleListener(final Level level) {
    39          this(level, System.out);
    40      }
    41
    42      /**
    43       * Creates the StatusConsoleListener using the supplied Level. Make sure not to use a logger stream of some sort
    44       * to avoid creating an infinite loop of indirection!
    45       * @param level The Level of status messages that should appear on the console.
    46       * @param stream The PrintStream to write to.
    47       * @throws IllegalArgumentException if the PrintStream argument is {@code null}.
    48       */
    49      public StatusConsoleListener(final Level level, final PrintStream stream) {
    50          if (stream == null) {
    51              throw new IllegalArgumentException("You must provide a stream to use for this listener.");
    52          }
    53          this.level = level;
    54          this.stream = stream;
    55      }
    56
    57      /**
    58       * Sets the level to a new value.
    59       * @param level The new Level.
    60       */
    61      public void setLevel(final Level level) {
    62          this.level = level;
    63      }
    64
    65      /**
    66       * Return the Log Level for which the Listener should receive events.
    67       * @return the Log Level.
    68       */
    69      @Override
    70      public Level getStatusLevel() {
    71          return this.level;
    72      }
    73
    74      /**
    75       * Writes status messages to the console.
    76       * @param data The StatusData.
    77       */
    78      @Override
    79      public void log(final StatusData data) {
    80          if (!filtered(data)) {
    81              stream.println(data.getFormattedStatus());
    82          }
    83      }
    84
    85      /**
    86       * Adds package name filters to exclude.
    87       * @param filters An array of package names to exclude.
    88       */
    89      public void setFilters(final String... filters) {
    90          this.filters = filters;
    91      }
    92
    93      private boolean filtered(final StatusData data) {
    94          if (filters == null) {
    95              return false;
    96          }
    97          final String caller = data.getStackTraceElement().getClassName();
    98          for (final String filter : filters) {
    99              if (caller.startsWith(filter)) {
    100                 return true;
    101             }
    102         }
    103         return false;
    104     }
    105
    106     @Override
    107     public void close() throws IOException {
    108         // only want to close non-system streams
    109         if (this.stream != System.out && this.stream != System.err) {
    110             this.stream.close();
    111         }
    112     }
    113 }