1 import java.io.IOException;
 2 import javassist.*;
 3
 4 public class TriangleJssistTiming {
 5     public static void main(String argv[]){
 6              try {
 7                      String classname="Triangle";
 8                      //获取class文件
 9                     CtClass clas =ClassPool.getDefault().get(classname);
10
11                     if(clas==null){
12                         System.out.println("classname"+clas+"  not found.");
13                     }else{
14                         //调用方法
15                         addTiming(clas,"isTriangle");
16                         addTiming(clas,"getType");
17                         addTiming(clas,"diffOfBorders");
18                         addTiming(clas,"getBorders");
19                         clas.writeFile();
20                     }
21                 } catch (CannotCompileException ex) {
22                     ex.printStackTrace();
23                 } catch (NotFoundException ex) {
24                     ex.printStackTrace();
25                 } catch (IOException ex) {
26                     ex.printStackTrace();
27                 }
28
29
30     }
31
32     private static void addTiming(CtClass cct,String method) throws NotFoundException, CannotCompileException{
33          //获取方法信息,如果方法不存在，则抛出异常
34         CtMethod ctMethod = cct.getDeclaredMethod(method);
35          //将旧的方法名称进行重新命名
36         String nname = method + "$impl";
37         ctMethod.setName(nname);
38         //方法的副本，采用过滤器的方式
39         CtMethod newCtMethod = CtNewMethod.copy(ctMethod, method, cct, null);
40
41         //为该方法添加时间过滤器来计算时间，并判断获取时间的方法是否有返回值
42         String type = ctMethod.getReturnType().getName();
43         StringBuffer body = new StringBuffer();
44         body.append("{\n long start = System.currentTimeMillis();\n");
45
46         body.append("System.out.println(\" "+ nname +"_in_11\");");
47         //返回值类型不同
48         if(!"void".equals(type)) {
49             body.append(type + " result = ");
50         }
51       //可以通过$$将传递给拦截器的参数，传递给原来的方法
52         body.append(nname + "($$);\n");
53        //输出方法运行时间差
54       //  body.append("System.out.println(\"Call to method " + nname + " took \" + \n (System.currentTimeMillis()-start) + " +  "\" ms.\");\n");
55         body.append("System.out.println(\" "+ nname +"_out_11\");");
56         if(!"void".equals(type)) {
57             body.append("return result;\n");
58         }
59
60         body.append("}");
61         //替换拦截器方法的主体内容，并将该方法添加到class之中
62         newCtMethod.setBody(body.toString());
63         cct.addMethod(newCtMethod);
64
65         //输出拦截器的代码块
66         System.out.println("拦截器方法的主体:");
67         System.out.println(body.toString());
68     }
69 }

  1 import java.io.PrintStream;
  2
  3 public class Triangle
  4 {
  5   public static void main(String[] args)
  6   {
  7     Triangle tr = new Triangle(2L, 3L, 4L);
  8     tr.isTriangle(tr);
  9   }
 10
 11   protected long lborderA = 0L;
 12   protected long lborderB = 0L;
 13   protected long lborderC = 0L;
 14
 15   public Triangle(long lborderA, long lborderB, long lborderC)
 16   {
 17     this.lborderA = lborderA;
 18
 19     this.lborderB = lborderB;
 20
 21     this.lborderC = lborderC;
 22   }
 23
 24   public boolean isTriangle$impl(Triangle triangle)
 25   {
 26     boolean isTriangle = false;
 27     if ((triangle.lborderA > 0L) && (triangle.lborderA <= 9223372036854775807L) &&
 28       (triangle.lborderB > 0L) && (triangle.lborderB <= 9223372036854775807L) &&
 29       (triangle.lborderC > 0L) && (triangle.lborderC <= 9223372036854775807L)) {
 30       if ((diffOfBorders(triangle.lborderA, triangle.lborderB) < triangle.lborderC) &&
 31         (diffOfBorders(triangle.lborderB, triangle.lborderC) < triangle.lborderA) &&
 32         (diffOfBorders(triangle.lborderC, triangle.lborderA) < triangle.lborderB)) {
 33         isTriangle = true;
 34       }
 35     }
 36     return isTriangle;
 37   }
 38
 39   public String getType$impl(Triangle triangle)
 40   {
 41     String strType = "Illegal";
 42     if (isTriangle(triangle)) {
 43       if ((triangle.lborderA == triangle.lborderB) &&
 44         (triangle.lborderB == triangle.lborderC)) {
 45         strType = "Regular";
 46       } else if ((triangle.lborderA != triangle.lborderB) &&
 47         (triangle.lborderB != triangle.lborderC) &&
 48         (triangle.lborderA != triangle.lborderC)) {
 49         strType = "Scalene";
 50       } else {
 51         strType = "Isosceles";
 52       }
 53     }
 54     return strType;
 55   }
 56
 57   public long diffOfBorders$impl(long a, long b)
 58   {
 59     return a > b ? a - b : b - a;
 60   }
 61
 62   public long[] getBorders$impl()
 63   {
 64     long[] borders = new long[3];
 65     borders[0] = this.lborderA;
 66     borders[1] = this.lborderB;
 67     borders[2] = this.lborderC;
 68     return borders;
 69   }
 70
 71   public boolean isTriangle(Triangle paramTriangle)
 72   {
 73     long l = System.currentTimeMillis();
 74     System.out.println(" isTriangle$impl_in_11");
 75     boolean bool = isTriangle$impl(paramTriangle);
 76     System.out.println(" isTriangle$impl_out_11");
 77     return bool;
 78   }
 79
 80   public String getType(Triangle paramTriangle)
 81   {
 82     long l = System.currentTimeMillis();
 83     System.out.println(" getType$impl_in_11");
 84     String str = getType$impl(paramTriangle);
 85     System.out.println(" getType$impl_out_11");
 86     return str;
 87   }
 88
 89   public long diffOfBorders(long paramLong1, long paramLong2)
 90   {
 91     long l1 = System.currentTimeMillis();
 92     System.out.println(" diffOfBorders$impl_in_11");
 93     long l2 = diffOfBorders$impl(paramLong1, paramLong2);
 94     System.out.println(" diffOfBorders$impl_out_11");
 95     return l2;
 96   }
 97
 98   public long[] getBorders()
 99   {
100     long l = System.currentTimeMillis();
101     System.out.println(" getBorders$impl_in_11");
102     long[] arrayOfLong = getBorders$impl();
103     System.out.println(" getBorders$impl_out_11");
104     return arrayOfLong;
105   }
106 }