Groovy example source code file (ModuleNode.java)

This example Groovy source code file (ModuleNode.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Groovy tags/keywords

acc_public, arraylist, blockstatement, classnode, classnode, importnode, importnode, io, list, list, map, methodnode, string, string, util, variableexpression

The Groovy ModuleNode.java source code

/*
 * Copyright 2003-2011 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.codehaus.groovy.ast;

import groovy.lang.Binding;
import org.codehaus.groovy.ast.expr.ArgumentListExpression;
import org.codehaus.groovy.ast.expr.ClassExpression;
import org.codehaus.groovy.ast.expr.MethodCallExpression;
import org.codehaus.groovy.ast.expr.VariableExpression;
import org.codehaus.groovy.ast.stmt.BlockStatement;
import org.codehaus.groovy.ast.stmt.ExpressionStatement;
import org.codehaus.groovy.ast.stmt.Statement;
import org.codehaus.groovy.control.SourceUnit;
import org.codehaus.groovy.runtime.InvokerHelper;
import org.objectweb.asm.Opcodes;

import java.io.File;
import java.util.*;

/**
 * Represents a module, which consists typically of a class declaration
 * but could include some imports, some statements and multiple classes
 * intermixed with statements like scripts in Python or Ruby
 *
 * @author Jochen Theodorou
 * @author Paul King
 * @author <a href="mailto:james@coredevelopers.net">James Strachan
 */
public class ModuleNode extends ASTNode implements Opcodes {

    private BlockStatement statementBlock = new BlockStatement();
    List<ClassNode> classes = new LinkedList();
    private List<MethodNode> methods = new ArrayList();
    private Map<String, ImportNode> imports = new HashMap();
    private List<ImportNode> starImports = new ArrayList();
    private Map<String, ImportNode> staticImports = new LinkedHashMap();
    private Map<String, ImportNode> staticStarImports = new LinkedHashMap();
    private CompileUnit unit;
    private PackageNode packageNode;
    private String description;
    private boolean createClassForStatements = true;
    private transient SourceUnit context;
    private boolean importsResolved = false;
    private ClassNode scriptDummy;
    private String mainClassName = null;

    public ModuleNode (SourceUnit context ) {
        this.context = context;
    }

    public ModuleNode (CompileUnit unit) {
        this.unit = unit;
    }

    public BlockStatement getStatementBlock() {
        return statementBlock;
    }

    public List<MethodNode> getMethods() {
        return methods;
    }

    public List<ClassNode> getClasses() {
        if (createClassForStatements && (!statementBlock.isEmpty() || !methods.isEmpty() || isPackageInfo())) {
            ClassNode mainClass = createStatementsClass();
            mainClassName = mainClass.getName(); 
            createClassForStatements = false;
            classes.add(0, mainClass);
            mainClass.setModule(this);
            addToCompileUnit(mainClass);
        }
        return classes;
    }

    private boolean isPackageInfo() {
        return context != null && context.getName() != null && context.getName().endsWith("package-info.groovy");
    }

    public List<ImportNode> getImports() {
        return new ArrayList<ImportNode>(imports.values());
    }

    public List<ImportNode> getStarImports() {
        return starImports;
    }

    /**
     * @param alias the name of interest
     * @return the class node for the given alias or null if none is available
     */
    public ClassNode getImportType(String alias) {
        ImportNode importNode = imports.get(alias);
        return importNode == null ? null : importNode.getType();
    }

    /**
     * @param alias the name of interest
     * @return the import node for the given alias or null if none is available
     */
    public ImportNode getImport(String alias) {
        return imports.get(alias);
    }

    public void addImport(String alias, ClassNode type) {
        addImport(alias, type, new ArrayList<AnnotationNode>());
    }

    public void addImport(String alias, ClassNode type, List<AnnotationNode> annotations) {
        ImportNode importNode = new ImportNode(type, alias);
        imports.put(alias, importNode);
        importNode.addAnnotations(annotations);
    }

    public void addStarImport(String packageName) {
        addStarImport(packageName, new ArrayList<AnnotationNode>());
    }

    public void addStarImport(String packageName, List<AnnotationNode> annotations) {
        ImportNode importNode = new ImportNode(packageName);
        importNode.addAnnotations(annotations);
        starImports.add(importNode);
    }

    public void addStatement(Statement node) {
        statementBlock.addStatement(node);
    }

    public void addClass(ClassNode node) {
        if(classes.isEmpty()) mainClassName = node.getName();
        classes.add(node);
        node.setModule(this);
        addToCompileUnit(node);
    }

    private void addToCompileUnit(ClassNode node) {
        // register the new class with the compile unit
        if (unit != null) {
            unit.addClass(node);
        }
    }

    public void addMethod(MethodNode node) {
        methods.add(node);
    }

    public void visit(GroovyCodeVisitor visitor) {
    }

    public String getPackageName() {
        return packageNode == null ? null : packageNode.getName();
    }

    public PackageNode getPackage() {
        return packageNode;
    }

    // TODO don't allow override?
    public void setPackage(PackageNode packageNode) {
        this.packageNode = packageNode;
    }

    // TODO don't allow override?
    public void setPackageName(String packageName) {
        this.packageNode = new PackageNode(packageName);
    }

    public boolean hasPackageName(){
        return packageNode != null && packageNode.getName() != null;
    }

    public boolean hasPackage(){
        return this.packageNode != null;
    }

    public SourceUnit getContext() {
        return context;
    }

    /**
     * @return the underlying character stream description
     */
    public String getDescription() {
        if( context != null )
        {
            return context.getName();
        }
        else
        {
            return this.description;
        }
    }

    public void setDescription(String description) {
        // DEPRECATED -- context.getName() is now sufficient
        // TODO add deprecated annotation or javadoc comment?
        this.description = description;
    }

    public CompileUnit getUnit() {
        return unit;
    }

    void setUnit(CompileUnit unit) {
        this.unit = unit;
    }

    public ClassNode getScriptClassDummy() {
        if (scriptDummy!=null) {
            setScriptBaseClassFromConfig(scriptDummy);
            return scriptDummy;
        }
        
        String name = getPackageName();
        if (name == null) {
            name = "";
        }
        // now let's use the file name to determine the class name
        if (getDescription() == null) {
            throw new RuntimeException("Cannot generate main(String[]) class for statements when we have no file description");
        }
        name += extractClassFromFileDescription();

        ClassNode classNode;
        if (isPackageInfo()) {
            classNode = new ClassNode(name, ACC_ABSTRACT | ACC_INTERFACE, ClassHelper.OBJECT_TYPE);
        } else {
            classNode = new ClassNode(name, ACC_PUBLIC, ClassHelper.SCRIPT_TYPE);
            setScriptBaseClassFromConfig(classNode);
            classNode.setScript(true);
            classNode.setScriptBody(true);
        }

        scriptDummy = classNode;
        return classNode;
    }
    
    private void setScriptBaseClassFromConfig(ClassNode cn) {
        if (unit != null) {
            String baseClassName = unit.getConfig().getScriptBaseClass();
            if(baseClassName != null) {
                if(!cn.getSuperClass().getName().equals(baseClassName)) {
                    cn.setSuperClass(ClassHelper.make(baseClassName));
                }
            }
        }
    }
    
    protected ClassNode createStatementsClass() {
        ClassNode classNode = getScriptClassDummy();
        if (classNode.getName().endsWith("package-info")) {
            return classNode;
        }
        
        handleMainMethodIfPresent(methods);

        // return new Foo(new ShellContext(args)).run()
        classNode.addMethod(
            new MethodNode(
                "main",
                ACC_PUBLIC | ACC_STATIC,
                ClassHelper.VOID_TYPE,
                new Parameter[] { new Parameter(ClassHelper.STRING_TYPE.makeArray(), "args")},
                ClassNode.EMPTY_ARRAY,
                new ExpressionStatement(
                    new MethodCallExpression(
                        new ClassExpression(ClassHelper.make(InvokerHelper.class)),
                        "runScript",
                        new ArgumentListExpression(
                                new ClassExpression(classNode),
                                new VariableExpression("args"))))));

        classNode.addMethod(
            new MethodNode("run", ACC_PUBLIC, ClassHelper.OBJECT_TYPE, Parameter.EMPTY_ARRAY, ClassNode.EMPTY_ARRAY, statementBlock));

        classNode.addConstructor(ACC_PUBLIC, Parameter.EMPTY_ARRAY, ClassNode.EMPTY_ARRAY, new BlockStatement());
        Statement stmt = new ExpressionStatement(
                        new MethodCallExpression(
                            new VariableExpression("super"),
                            "setBinding",
                            new ArgumentListExpression(
                                        new VariableExpression("context"))));

        classNode.addConstructor(
            ACC_PUBLIC,
            new Parameter[] { new Parameter(ClassHelper.make(Binding.class), "context")},
            ClassNode.EMPTY_ARRAY,
            stmt);

        for (MethodNode node : methods) {
            int modifiers = node.getModifiers();
            if ((modifiers & ACC_ABSTRACT) != 0) {
                throw new RuntimeException(
                    "Cannot use abstract methods in a script, they are only available inside classes. Method: "
                        + node.getName());
            }
            // br: the old logic seems to add static to all def f().... in a script, which makes enclosing
            // inner classes (including closures) in a def function difficult. Comment it out.
            node.setModifiers(modifiers /*| ACC_STATIC*/);

            classNode.addMethod(node);
        }
        return classNode;
    }

    /*
     * If a main method is provided by user, account for it under run() as scripts generate their own 'main' so they can run.  
     */
    private void handleMainMethodIfPresent(List methods) {
        boolean found = false;
        for (Iterator iter = methods.iterator(); iter.hasNext();) {
            MethodNode node = (MethodNode) iter.next();
            if(node.getName().equals("main")) {
                int modifiers = node.getModifiers();
                if (node.isStatic() && node.getParameters().length == 1) {
                    boolean retTypeMatches, argTypeMatches;
                    ClassNode argType = node.getParameters()[0].getType();
                    ClassNode retType = node.getReturnType();

                    argTypeMatches = (argType.equals(ClassHelper.OBJECT_TYPE) || argType.getName().contains("String[]"));
                    retTypeMatches = (retType == ClassHelper.VOID_TYPE || retType == ClassHelper.OBJECT_TYPE);
                    
                    if(retTypeMatches && argTypeMatches) {
                        if(found) {
                            throw new RuntimeException("Repetitive main method found.");
                        } else {
                            found = true;
                        }
                        // if script has both loose statements as well as main(), then main() is ignored
                        if(statementBlock.isEmpty()) {
                            addStatement(node.getCode());
                        }
                        iter.remove();
                    }
                }
            }
        }
    }

    protected String extractClassFromFileDescription() {
        // let's strip off everything after the last '.'
        String answer = getDescription();
        int slashIdx = answer.lastIndexOf('/');
        int separatorIdx = answer.lastIndexOf(File.separatorChar);
        int dotIdx = answer.lastIndexOf('.');
        if (dotIdx > 0 && dotIdx > Math.max(slashIdx, separatorIdx)) {
            answer = answer.substring(0, dotIdx);
        }
        // new let's strip everything up to and including the path separators
        if (slashIdx >= 0) {
            answer = answer.substring(slashIdx + 1);
        }
        // recalculate in case we have already done some stripping
        separatorIdx = answer.lastIndexOf(File.separatorChar);
        if (separatorIdx >= 0) {
            answer = answer.substring(separatorIdx + 1);
        }
        return answer;
    }

    public boolean isEmpty() {
        return classes.isEmpty() && statementBlock.getStatements().isEmpty();
    }
    
    public void sortClasses(){
        if (isEmpty()) return;
        List<ClassNode> classes = getClasses();
        LinkedList<ClassNode> sorted = new LinkedList();
        int level=1;
        while (!classes.isEmpty()) {
            for (Iterator<ClassNode> cni = classes.iterator(); cni.hasNext();) {
                ClassNode cn = cni.next();
                ClassNode sn = cn;
                for (int i=0; sn!=null && i<level; i++) sn = sn.getSuperClass();
                if (sn!=null && sn.isPrimaryClassNode()) continue;
                cni.remove();
                sorted.addLast(cn);
            }
            level++;
        }
        this.classes = sorted;
    }

    public boolean hasImportsResolved() {
        return importsResolved;
    }

    public void setImportsResolved(boolean importsResolved) {
        this.importsResolved = importsResolved;
    }

    public Map<String, ImportNode> getStaticImports() {
        return staticImports;
    }

    public Map<String, ImportNode> getStaticStarImports() {
        return staticStarImports;
    }

    public void addStaticImport(ClassNode type, String fieldName, String alias) {
        addStaticImport(type, fieldName, alias, new ArrayList<AnnotationNode>());
    }

    public void addStaticImport(ClassNode type, String fieldName, String alias, List<AnnotationNode> annotations) {
        ImportNode node = new ImportNode(type, fieldName, alias);
        node.addAnnotations(annotations);
        staticImports.put(alias, node);
    }

    public void addStaticStarImport(String name, ClassNode type) {
        addStaticStarImport(name, type, new ArrayList<AnnotationNode>());
    }

    public void addStaticStarImport(String name, ClassNode type, List<AnnotationNode> annotations) {
        ImportNode node = new ImportNode(type);
        node.addAnnotations(annotations);
        staticStarImports.put(name, node);
    }
    
    public String getMainClassName() {
        return mainClassName;
    }
}