LogService: Add LogLevel class to organize logging levels

Author: ctrueden

src/main/java/org/scijava/log/AbstractLogService.java

@@ -107,27 +107,10 @@ protected void log(final int level, final Object msg, final Throwable t) {
 	}
 
 	protected void log(final int level, final Object msg) {
-		final String prefix = getPrefix(level);
+		final String prefix = LogLevel.prefix(level);
 		log((prefix == null ? "" : prefix + " ") + msg);
 	}
 
-	protected String getPrefix(final int level) {
-		switch (level) {
-			case ERROR:
-				return "[ERROR]";
-			case WARN:
-				return "[WARNING]";
-			case INFO:
-				return "[INFO]";
-			case DEBUG:
-				return "[DEBUG]";
-			case TRACE:
-				return "[TRACE]";
-			default:
-				return null;
-		}
-	}
-
 	// -- LogService methods --
 
 	@Override
@@ -255,6 +238,14 @@ public void setLevel(final String classOrPackageName, final int level) {
 		classAndPackageLevels.put(classOrPackageName, level);
 	}
 
+	// -- Deprecated --
+
+	/** @deprecated Use {@link LogLevel#prefix(int)} instead. */
+	@Deprecated
+	protected String getPrefix(final int level) {
+		return "[" + LogLevel.prefix(level) + "]";
+	}
+
 	// -- Helper methods --
 
 	/** Extracts the log level value from a string. */

src/main/java/org/scijava/log/LogLevel.java

@@ -0,0 +1,68 @@
+/*
+ * #%L
+ * SciJava Common shared library for SciJava software.
+ * %%
+ * Copyright (C) 2009 - 2017 Board of Regents of the University of
+ * Wisconsin-Madison, Broad Institute of MIT and Harvard, and Max Planck
+ * Institute of Molecular Cell Biology and Genetics.
+ * %%
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ * 
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ * #L%
+ */
+
+package org.scijava.log;
+
+/**
+ * Constants for specifying a logger's level of verbosity.
+ * 
+ * @author Curtis Rueden
+ */
+public final class LogLevel {
+
+	private LogLevel() {
+		// prevent instantiation of utility class
+	}
+
+	public static final int NONE = 0;
+	public static final int ERROR = 1;
+	public static final int WARN = 2;
+	public static final int INFO = 3;
+	public static final int DEBUG = 4;
+	public static final int TRACE = 5;
+
+	public static String prefix(final int level) {
+		switch (level) {
+			case ERROR:
+				return "ERROR";
+			case WARN:
+				return "WARNING";
+			case INFO:
+				return "INFO";
+			case DEBUG:
+				return "DEBUG";
+			case TRACE:
+				return "TRACE";
+			default:
+				return "LEVEL" + level;
+		}
+	}
+}

src/main/java/org/scijava/log/LogService.java

@@ -50,12 +50,26 @@ public interface LogService extends SciJavaService {
 	/** System property to set for overriding the default logging level. */
 	String LOG_LEVEL_PROPERTY = "scijava.log.level";
 
-	int NONE = 0;
-	int ERROR = 1;
-	int WARN = 2;
-	int INFO = 3;
-	int DEBUG = 4;
-	int TRACE = 5;
+	// -- Deprecated --
+
+	/** @deprecated Use {@link LogLevel#NONE}. */
+	@Deprecated
+	int NONE = LogLevel.NONE;
+	/** @deprecated Use {@link LogLevel#ERROR}. */
+	@Deprecated
+	int ERROR = LogLevel.ERROR;
+	/** @deprecated Use {@link LogLevel#WARN}. */
+	@Deprecated
+	int WARN = LogLevel.WARN;
+	/** @deprecated Use {@link LogLevel#INFO}. */
+	@Deprecated
+	int INFO = LogLevel.INFO;
+	/** @deprecated Use {@link LogLevel#DEBUG}. */
+	@Deprecated
+	int DEBUG = LogLevel.DEBUG;
+	/** @deprecated Use {@link LogLevel#TRACE}. */
+	@Deprecated
+	int TRACE = LogLevel.TRACE;
 
 	void debug(Object msg);
 

src/main/java/org/scijava/log/StderrLogService.java

@@ -52,7 +52,7 @@ public class StderrLogService extends AbstractLogService {
 
 	@Override
 	protected void log(final int level, final Object msg) {
-		final String prefix = getPrefix(level);
+		final String prefix = LogLevel.prefix(level);
 		final String message = (prefix == null ? "" : prefix + " ") + msg;
 		// NB: Emit severe messages to stderr, and less severe ones to stdout.
 		if (level <= WARN) System.err.println(message);