动态编译java源代码及反射调用问题

Question

package com.tom.labs;

import java.io.IOException;
import java.lang.reflect.Method;
import java.net.URI;
import java.net.URISyntaxException;
import java.util.Arrays;

import javax.tools.JavaCompiler;
import javax.tools.JavaCompiler.CompilationTask;
import javax.tools.SimpleJavaFileObject;
import javax.tools.StandardJavaFileManager;
import javax.tools.ToolProvider;

public class CompilerTest {

    /**
     * @param args
     */
    public static void main(String[] args) throws Exception {
        String source = "public class Main { " +
                " public static void main(String[] args) {" +
                "   System.out.println(\"Hello World!\");" +
                " }" +
                " public static void test() { " +
                " System.out.println(\"Hello World!\");" +
                " } " +
                "}";
        JavaCompiler compiler = ToolProvider.getSystemJavaCompiler();
        StandardJavaFileManager fileManager = compiler.getStandardFileManager(null, null, null);
        StringSourceJavaObject sourceObject = new CompilerTest.StringSourceJavaObject("Main", source);
        Iterable fileObjects = Arrays.asList(sourceObject);
        CompilationTask task = compiler.getTask(null, fileManager, null, null, null, fileObjects);
        boolean result = task.call();
        if (result) {
            ClassLoader loader = CompilerTest.class.getClassLoader();
            Class<?> clazz = loader.loadClass("com.tom.labs.Main");
            Method method = clazz.getMethod("test", new Class<?>[] {});
            method.invoke(null, new Object[] {});
        }
    }

    static class StringSourceJavaObject extends SimpleJavaFileObject {
        private String content = null;
        public StringSourceJavaObject(String name, String content) throws URISyntaxException {
            super(URI.create("string:///" + name.replace('.', '/') + Kind.SOURCE.extension), Kind.SOURCE);
            this.content = content;
        }
        public CharSequence getCharContent(boolean ignoreEncodingErrors) throws IOException {
            return content;
        }
    }
}

有人能帮我吗？更新：

我打印出了getMethods的输出:[public static void com.tom.labs.main.main(java.lang.String[]),public final void java.lang.object.wait（long,int）抛出java.lang.interruptedexception,public final native void java.lang.object.wait（long）抛出java.lang.interruptedexception,public final void java.lang.object.wait（）抛出java.lang.interruptedexception,public

很奇怪，方法测试不在里面。

Answer 1

您的“来源”

String source = "public class Main { " +
                " public static void main(String[] args) {" +
                "   System.out.println(\"Hello World!\");" +
                " }" +
                " public static void test() { " +
                " System.out.println(\"Hello World!\");" +
                " } " +
                "}";

没有命名空间。您应该向其添加一个package关键字，或者更改

Class<?> clazz = loader.loadClass("com.tom.labs.Main");

至

Class<?> clazz = loader.loadClass("Main");