/*
* Copyright 2010 the original author or authors.
*
* Licensed 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 org.gradle.groovy.scripts;
import groovy.lang.GroovyClassLoader;
import groovy.lang.GroovyCodeSource;
import groovy.lang.Script;
import groovyjarjarasm.asm.ClassWriter;
import org.apache.commons.lang.StringUtils;
import org.codehaus.groovy.ast.expr.ConstantExpression;
import org.codehaus.groovy.ast.stmt.ReturnStatement;
import org.codehaus.groovy.ast.stmt.Statement;
import org.codehaus.groovy.control.*;
import org.codehaus.groovy.syntax.SyntaxException;
import org.gradle.api.GradleException;
import org.gradle.api.ScriptCompilationException;
import org.gradle.util.Clock;
import org.gradle.util.GFileUtils;
import org.gradle.util.WrapUtil;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.io.File;
import java.net.URLClassLoader;
import java.security.CodeSource;
import java.util.List;
/**
* @author Hans Dockter
*/
public class DefaultScriptCompilationHandler implements ScriptCompilationHandler {
private Logger logger = LoggerFactory.getLogger(DefaultScriptCompilationHandler.class);
private static final String EMPTY_SCRIPT_MARKER_FILE_NAME = "emptyScript.txt";
public void compileToDir(ScriptSource source, ClassLoader classLoader, File classesDir,
Transformer transformer, Class<? extends Script> scriptBaseClass) {
Clock clock = new Clock();
GFileUtils.deleteDirectory(classesDir);
classesDir.mkdirs();
CompilerConfiguration configuration = createBaseCompilerConfiguration(scriptBaseClass);
configuration.setTargetDirectory(classesDir);
try {
compileScript(source, classLoader, configuration, classesDir, transformer);
} catch (GradleException e) {
GFileUtils.deleteDirectory(classesDir);
throw e;
}
logger.debug("Timing: Writing script to cache at {} took: {}", classesDir.getAbsolutePath(),
clock.getTime());
}
private void compileScript(final ScriptSource source, ClassLoader classLoader, CompilerConfiguration configuration,
File classesDir, final Transformer transformer) {
logger.info("Compiling {} using {}.", source.getDisplayName(), transformer != null ? transformer.getClass().getSimpleName() : "no transformer");
final EmptyScriptDetector emptyScriptDetector = new EmptyScriptDetector();
final PackageStatementDetector packageDetector = new PackageStatementDetector();
GroovyClassLoader groovyClassLoader = new GroovyClassLoader(classLoader, configuration, false) {
@Override
protected CompilationUnit createCompilationUnit(CompilerConfiguration compilerConfiguration,
CodeSource codeSource) {
CompilationUnit compilationUnit = new CompilationUnit(compilerConfiguration, codeSource, this) {
// This creepy bit of code is here to put the full source path of the script into the debug info for
// the class. This makes it possible for a debugger to find the source file for the class. By default
// Groovy will only put the filename into the class, but that does not help a debugger for Gradle
// because it does not know where Gradle scripts might live.
@Override
protected groovyjarjarasm.asm.ClassVisitor createClassVisitor() {
return new ClassWriter(ClassWriter.COMPUTE_MAXS) {
// ignore the sourcePath that is given by Groovy (this is only the filename) and instead
// insert the full path if our script source has a source file
@Override
public void visitSource(String sourcePath, String debugInfo) {
super.visitSource(source.getFileName(), debugInfo);
}
};
}
};
if (transformer != null) {
transformer.register(compilationUnit);
}
compilationUnit.addPhaseOperation(packageDetector, Phases.CANONICALIZATION);
compilationUnit.addPhaseOperation(emptyScriptDetector, Phases.CANONICALIZATION);
return compilationUnit;
}
};
String scriptText = source.getResource().getText();
String scriptName = source.getClassName();
GroovyCodeSource codeSource = new GroovyCodeSource(scriptText == null ? "" : scriptText, scriptName, "/groovy/script");
try {
groovyClassLoader.parseClass(codeSource, false);
} catch (MultipleCompilationErrorsException e) {
SyntaxException syntaxError = e.getErrorCollector().getSyntaxError(0);
Integer lineNumber = syntaxError == null ? null : syntaxError.getLine();
throw new ScriptCompilationException(String.format("Could not compile %s.", source.getDisplayName()), e, source,
lineNumber);
} catch (CompilationFailedException e) {
throw new GradleException(String.format("Could not compile %s.", source.getDisplayName()), e);
}
if (packageDetector.hasPackageStatement) {
throw new UnsupportedOperationException(String.format("%s should not contain a package statement.",
StringUtils.capitalize(source.getDisplayName())));
}
if (emptyScriptDetector.isEmptyScript()) {
GFileUtils.touch(new File(classesDir, EMPTY_SCRIPT_MARKER_FILE_NAME));
}
}
private CompilerConfiguration createBaseCompilerConfiguration(Class<? extends Script> scriptBaseClass) {
CompilerConfiguration configuration = new CompilerConfiguration();
configuration.setScriptBaseClass(scriptBaseClass.getName());
return configuration;
}
public <T extends Script> Class<? extends T> loadFromDir(ScriptSource source, ClassLoader classLoader, File scriptCacheDir,
Class<T> scriptBaseClass) {
if (new File(scriptCacheDir, EMPTY_SCRIPT_MARKER_FILE_NAME).isFile()) {
return new AsmBackedEmptyScriptGenerator().generate(scriptBaseClass);
}
try {
URLClassLoader urlClassLoader = new URLClassLoader(WrapUtil.toArray(scriptCacheDir.toURI().toURL()),
classLoader);
return urlClassLoader.loadClass(source.getClassName()).asSubclass(scriptBaseClass);
} catch (Exception e) {
throw new GradleException(String.format("Could not load compiled classes for %s from cache.",
source.getDisplayName()), e);
}
}
private static class PackageStatementDetector extends CompilationUnit.SourceUnitOperation {
private boolean hasPackageStatement;
@Override
public void call(SourceUnit source) throws CompilationFailedException {
hasPackageStatement = source.getAST().getPackageName() != null;
}
}
private static class EmptyScriptDetector extends CompilationUnit.SourceUnitOperation {
private boolean emptyScript;
@Override
public void call(SourceUnit source) throws CompilationFailedException {
emptyScript = isEmpty(source);
}
private boolean isEmpty(SourceUnit source) {
if (!source.getAST().getMethods().isEmpty()) {
return false;
}
List<Statement> statements = source.getAST().getStatementBlock().getStatements();
if (statements.size() > 1) {
return false;
}
if (statements.isEmpty()) {
return true;
}
Statement statement = statements.get(0);
if (statement instanceof ReturnStatement) {
ReturnStatement returnStatement = (ReturnStatement) statement;
if (returnStatement.getExpression() instanceof ConstantExpression) {
ConstantExpression constantExpression = (ConstantExpression) returnStatement.getExpression();
if (constantExpression.getValue() == null) {
return true;
}
}
}
return false;
}
public boolean isEmptyScript() {
return emptyScript;
}
}
}