groovy.util.logging.Log Maven / Gradle / Ivy
/*
* 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 groovy.util.logging;
import groovy.lang.GroovyClassLoader;
import org.codehaus.groovy.ast.ClassHelper;
import org.codehaus.groovy.ast.ClassNode;
import org.codehaus.groovy.ast.FieldNode;
import org.codehaus.groovy.ast.expr.ArgumentListExpression;
import org.codehaus.groovy.ast.expr.AttributeExpression;
import org.codehaus.groovy.ast.expr.BooleanExpression;
import org.codehaus.groovy.ast.expr.ClassExpression;
import org.codehaus.groovy.ast.expr.ConstantExpression;
import org.codehaus.groovy.ast.expr.Expression;
import org.codehaus.groovy.ast.expr.MethodCallExpression;
import org.codehaus.groovy.ast.expr.TernaryExpression;
import org.codehaus.groovy.transform.GroovyASTTransformationClass;
import org.codehaus.groovy.transform.LogASTTransformation;
import org.codehaus.groovy.transform.LogASTTransformation.LoggingStrategy;
import org.objectweb.asm.Opcodes;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
import java.util.Locale;
/**
* This local transform adds a logging ability to your program using
* java.util.logging. Every method call on a unbound variable named log
* will be mapped to a call to the logger. For this a log field will be
* inserted in the class. If the field already exists the usage of this transform
* will cause a compilation error. The method name will be used to determine
* what to call on the logger.
*
* log.name(exp)
*
is mapped to
*
* if (log.isLoggable(Level.NAME) {
* log.name(exp)
* }
* Here name is a place holder for info, fine, finer, finest, config, warning, severe.
* NAME is name transformed to upper case. if anything else is used it will result in
* an exception at runtime. If the expression exp is a constant or only a variable access
* the method call will not be transformed. But this will still cause a call on the injected
* logger.
*
* @author Guillaume Laforge
* @author Jochen Theodorou
* @author Dinko Srkoc
* @author Hamlet D'Arcy
* @author Raffaele Cigni
* @author Alberto Vilches Raton
* @since 1.8.0
*/
@java.lang.annotation.Documented
@Retention(RetentionPolicy.SOURCE)
@Target({ElementType.TYPE})
@GroovyASTTransformationClass("org.codehaus.groovy.transform.LogASTTransformation")
public @interface Log {
String value() default "log";
String category() default LogASTTransformation.DEFAULT_CATEGORY_NAME;
Class loggingStrategy() default JavaUtilLoggingStrategy.class;
/**
* This class contains the logic of how to weave a Java Util Logging logger into the host class.
*/
public static class JavaUtilLoggingStrategy extends LogASTTransformation.AbstractLoggingStrategy {
private static final ClassNode LOGGER_CLASSNODE = ClassHelper.make(java.util.logging.Logger.class);
private static final ClassNode LEVEL_CLASSNODE = ClassHelper.make(java.util.logging.Level.class);
protected JavaUtilLoggingStrategy(final GroovyClassLoader loader) {
super(loader);
}
public FieldNode addLoggerFieldToClass(ClassNode classNode, String logFieldName, String categoryName) {
return classNode.addField(logFieldName,
Opcodes.ACC_FINAL | Opcodes.ACC_TRANSIENT | Opcodes.ACC_STATIC | Opcodes.ACC_PRIVATE,
LOGGER_CLASSNODE,
new MethodCallExpression(
new ClassExpression(LOGGER_CLASSNODE),
"getLogger",
new ConstantExpression(getCategoryName(classNode, categoryName))));
}
public boolean isLoggingMethod(String methodName) {
return methodName.matches("severe|warning|info|fine|finer|finest");
}
public Expression wrapLoggingMethodCall(Expression logVariable, String methodName, Expression originalExpression) {
AttributeExpression logLevelExpression = new AttributeExpression(
new ClassExpression(LEVEL_CLASSNODE),
new ConstantExpression(methodName.toUpperCase(Locale.ENGLISH)));
ArgumentListExpression args = new ArgumentListExpression();
args.addExpression(logLevelExpression);
MethodCallExpression condition = new MethodCallExpression(logVariable, "isLoggable", args);
condition.setImplicitThis(false);
return new TernaryExpression(
new BooleanExpression(condition),
originalExpression,
ConstantExpression.NULL);
}
}
}