java实现动态编译本地java文件
动态编译package file;import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.io.StringWriter;
import java.lang.reflect.Method;
import java.net.URL;
import java.net.URLClassLoader;
import javax.tools.JavaCompiler;
import javax.tools.StandardJavaFileManager;
import javax.tools.ToolProvider;
import javax.tools.JavaCompiler.CompilationTask;
public class DongTaiBianYi {
/**
* @param args
* @throws Exception
* ￥-824.40 -824.40
*/
public static void main(String[] args)throws Exception {
// TODO Auto-generated method stub
DongTaiBianYi dtby = new DongTaiBianYi();
//dtby.textJavaCompiler();
//dtby.textStringWrite();
}
public void textJavaCompiler() throws IOException{
// 编译程序
JavaCompiler javaCompiler = ToolProvider.getSystemJavaCompiler();
int result = javaCompiler.run(null, null, null, "-d","./src/","./src/file/MyText.java");
System.out.println( result == 0 ? "恭喜编译成功" : "对不起编译失败");
}
public void textStringWrite() throws Exception{
JavaCompiler complier = ToolProvider.getSystemJavaCompiler();
StandardJavaFileManager sjf =
complier.getStandardFileManager(null, null, null);
Iterable it = sjf.getJavaFileObjects("D:/Hello.java");
CompilationTask task = complier.getTask(null, sjf, null, null, null, it);
task.call();//调用创建,创建class文件
sjf.close();
URL urls[] = new URL[]{ new URL("file:/D:/")}; //储存文件目录的地址
URLClassLoader uLoad = new URLClassLoader(urls);//classloader从哪个目录找？
//uLoad.loadClass("Hello");
Class c = uLoad.loadClass("Hello");//找哪个class文件 注意不带后缀名
//c.newInstance();//创建一个实例
Method method = c.getMethod("printString");
String string = method.invoke(c.newInstance()).toString();
System.out.println(string);
}
}2.Hello.javapackage entity;
public class Hello {
public void printString(){
System.out.println("Hello word!");
}
}
页:
[1]