ParserTst.java

/**
 * BSD-style license; for more info see http://pmd.sourceforge.net/license.html
*/
package test.net.sourceforge.pmd.ast;

import junit.framework.TestCase;
import net.sourceforge.pmd.TargetJDK1_4;
import net.sourceforge.pmd.ast.ASTCompilationUnit;
import net.sourceforge.pmd.ast.JavaParser;
import net.sourceforge.pmd.ast.JavaParserVisitor;

import java.io.StringReader;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
import java.util.HashSet;
import java.util.Set;

public class ParserTst extends TestCase {

    private class Collector implements InvocationHandler {
        private Class clazz = null;
        private Set collection = new HashSet();

        public Collector(Class clazz) {
            this.clazz = clazz;
        }

        public Set getCollection() {
            return collection;
        }

        public Object invoke(Object proxy, Method method, Object params[]) throws Throwable {
            if (method.getName().equals("visit")) {
                if (clazz.isInstance(params[0])) {
                    collection.add(params[0]);
                }
            }

            Method childrenAccept = params[0].getClass().getMethod("childrenAccept", new Class[]{JavaParserVisitor.class, Object.class});
            childrenAccept.invoke(params[0], new Object[]{proxy, null});
            return null;
        }
    }

    public Set getNodes(Class clazz, String javaCode) throws Throwable {
        Collector coll = new Collector(clazz);
        JavaParser parser = (new TargetJDK1_4()).createParser(new StringReader(javaCode));
        ASTCompilationUnit cu = parser.CompilationUnit();
        JavaParserVisitor jpv = (JavaParserVisitor) Proxy.newProxyInstance(JavaParserVisitor.class.getClassLoader(), new Class[]{JavaParserVisitor.class}, coll);
        jpv.visit(cu, null);
        return coll.getCollection();
    }
}