1 /* 2 * Copyright (c) 2002-2012, the original author or authors. 3 * 4 * This software is distributable under the BSD license. See the terms of the 5 * BSD license in the documentation provided with this software. 6 * 7 * http://www.opensource.org/licenses/bsd-license.php 8 */ 9 package jdk.internal.jline.internal; 10 11 import java.io.PrintStream; 12 13 import static jdk.internal.jline.internal.Preconditions.checkNotNull; 14 15 /** 16 * Internal logger. 17 * 18 * @author <a href="mailto:jason@planet57.com">Jason Dillon</a> 19 * @since 2.0 20 */ 21 public final class Log 22 { 23 ///CLOVER:OFF 24 25 public static enum Level 26 { 27 TRACE, 28 DEBUG, 29 INFO, 30 WARN, 31 ERROR 32 } 33 34 @SuppressWarnings({"StringConcatenation"}) 35 public static final boolean TRACE = Boolean.getBoolean(Log.class.getName() + ".trace"); 36 37 @SuppressWarnings({"StringConcatenation"}) 38 public static final boolean DEBUG = TRACE || Boolean.getBoolean(Log.class.getName() + ".debug"); 39 40 private static PrintStream output = System.err; 41 42 public static PrintStream getOutput() { 43 return output; 44 } 45 46 public static void setOutput(final PrintStream out) { 47 output = checkNotNull(out); 48 } 49 50 /** 51 * Helper to support rendering messages. 52 */ 53 @TestAccessible 54 static void render(final PrintStream out, final Object message) { 55 if (message.getClass().isArray()) { 56 Object[] array = (Object[]) message; 57 58 out.print("["); 59 for (int i = 0; i < array.length; i++) { 60 out.print(array[i]); 61 if (i + 1 < array.length) { 62 out.print(","); 63 } 64 } 65 out.print("]"); 66 } 67 else { 68 out.print(message); 69 } 70 } 71 72 @TestAccessible 73 static void log(final Level level, final Object... messages) { 74 //noinspection SynchronizeOnNonFinalField 75 synchronized (output) { 76 output.format("[%s] ", level); 77 78 for (int i=0; i<messages.length; i++) { 79 // Special handling for the last message if its a throwable, render its stack on the next line 80 if (i + 1 == messages.length && messages[i] instanceof Throwable) { 81 output.println(); 82 ((Throwable)messages[i]).printStackTrace(output); 83 } 84 else { 85 render(output, messages[i]); 86 } 87 } 88 89 output.println(); 90 output.flush(); 91 } 92 } 93 94 public static void trace(final Object... messages) { 95 if (TRACE) { 96 log(Level.TRACE, messages); 97 } 98 } 99 100 public static void debug(final Object... messages) { 101 if (TRACE || DEBUG) { 102 log(Level.DEBUG, messages); 103 } 104 } 105 106 /** 107 * @since 2.7 108 */ 109 public static void info(final Object... messages) { 110 log(Level.INFO, messages); 111 } 112 113 public static void warn(final Object... messages) { 114 log(Level.WARN, messages); 115 } 116 117 public static void error(final Object... messages) { 118 log(Level.ERROR, messages); 119 } 120 }