import java.io.IOException;
import java.io.PrintWriter;
import javassist.CannotCompileException;
import javassist.ClassPool;
import javassist.CtClass;
import javassist.CtMethod;
import javassist.NotFoundException;
/**
* @author zhangruming
*
*/
public class calss2 {
/**
* @param args
* @throws NotFoundException
* @throws CannotCompileException
* @throws IllegalAccessException
* @throws InstantiationException
* @throws IOException
* @throws ClassNotFoundException
*/
public static void main(String[] args) throws NotFoundException, CannotCompileException, InstantiationException, IllegalAccessException, IOException, ClassNotFoundException {
ClassPool cp = ClassPool.getDefault();
CtClass cc = cp.get("calss1");
CtMethod cm = cc.getDeclaredMethod("sayhi");
cm.setBody("System.out.println(\"hi class1\");");
calss1 calss1 = (calss1) cc.toClass().newInstance();
calss1.kk();
String javaStr = "class calss3{public void sayhi(){System.out.println(\"hi!\");}}";
String className = "calss3";
PrintWriter writer = new PrintWriter(className + ".java");
writer.close();
Runtime.getRuntime().exec( "javac -d " + className + ".java ");
Class c = Class.forName(className);
calss3 o = (calss3) c.newInstance();
o.kk();
}
}
class calss1{
public void sayhi()
{
System.out.println("hi!");
}
}
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原文地址:http://www.cnblogs.com/zhangrumingbj/p/3884717.html