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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one
3    * or more contributor license agreements.  See the NOTICE file
4    * distributed with this work for additional information
5    * regarding copyright ownership.  The ASF licenses this file
6    * to you under the Apache License, Version 2.0 (the
7    * "License"); you may not use this file except in compliance
8    * with the License.  You may obtain a copy of the License at
9    *
10   *   http://www.apache.org/licenses/LICENSE-2.0
11   *
12   * Unless required by applicable law or agreed to in writing,
13   * software distributed under the License is distributed on an
14   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15   * KIND, either express or implied.  See the License for the
16   * specific language governing permissions and limitations
17   * under the License.
18   */
19  package org.slf4j.impl;
20  
21  import java.io.PrintStream;
22  
23  import org.apache.maven.api.services.MessageBuilder;
24  import org.apache.maven.cli.jansi.MessageUtils;
25  
26  /**
27   * Logger for Maven, that support colorization of levels and stacktraces. This class implements 2 methods introduced in
28   * slf4j-simple provider local copy.
29   *
30   * @since 3.5.0
31   */
32  public class MavenSimpleLogger extends SimpleLogger {
33      MavenSimpleLogger(String name) {
34          super(name);
35      }
36  
37      @Override
38      protected String renderLevel(int level) {
39          switch (level) {
40              case LOG_LEVEL_TRACE:
41                  return builder().debug("TRACE").build();
42              case LOG_LEVEL_DEBUG:
43                  return builder().debug("DEBUG").build();
44              case LOG_LEVEL_INFO:
45                  return builder().info("INFO").build();
46              case LOG_LEVEL_WARN:
47                  return builder().warning("WARNING").build();
48              case LOG_LEVEL_ERROR:
49              default:
50                  return builder().error("ERROR").build();
51          }
52      }
53  
54      @Override
55      protected void writeThrowable(Throwable t, PrintStream stream) {
56          if (t == null) {
57              return;
58          }
59          stream.print(builder().failure(t.getClass().getName()));
60          if (t.getMessage() != null) {
61              stream.print(": ");
62              stream.print(builder().failure(t.getMessage()));
63          }
64          stream.println();
65  
66          printStackTrace(t, stream, "");
67      }
68  
69      private void printStackTrace(Throwable t, PrintStream stream, String prefix) {
70          for (StackTraceElement e : t.getStackTrace()) {
71              stream.print(prefix);
72              stream.print("    ");
73              stream.print(builder().strong("at"));
74              stream.print(" " + e.getClassName() + "." + e.getMethodName());
75              stream.print(builder().a(" (").strong(getLocation(e)).a(")"));
76              stream.println();
77          }
78          for (Throwable se : t.getSuppressed()) {
79              writeThrowable(se, stream, "Suppressed", prefix + "    ");
80          }
81          Throwable cause = t.getCause();
82          if (cause != null) {
83              writeThrowable(cause, stream, "Caused by", prefix);
84          }
85      }
86  
87      private void writeThrowable(Throwable t, PrintStream stream, String caption, String prefix) {
88          stream.print(builder().a(prefix).strong(caption).a(": ").a(t.getClass().getName()));
89          if (t.getMessage() != null) {
90              stream.print(": ");
91              stream.print(builder().failure(t.getMessage()));
92          }
93          stream.println();
94  
95          printStackTrace(t, stream, prefix);
96      }
97  
98      protected String getLocation(final StackTraceElement e) {
99          assert e != null;
100 
101         if (e.isNativeMethod()) {
102             return "Native Method";
103         } else if (e.getFileName() == null) {
104             return "Unknown Source";
105         } else if (e.getLineNumber() >= 0) {
106             return String.format("%s:%s", e.getFileName(), e.getLineNumber());
107         } else {
108             return e.getFileName();
109         }
110     }
111 
112     private MessageBuilder builder() {
113         return MessageUtils.builder();
114     }
115 }