Java安全之自定义SecurityManager

package com.leasehouse;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.security.AccessControlException;

public class TestForkJoin {
    public static void main(String[] args) {
        System.setSecurityManager(new MySecurityManager());
        File file = new File("/Users/yulifan/Desktop/ff.exe");
      try {
          FileInputStream fileInputStream = new FileInputStream(file);
          byte[] cc = new byte[1024];
          //fileInputStream.read(cc);
      } catch (Exception e) {
        e.printStackTrace();
      }

    }
}

class MySecurityManager extends SecurityManager {
  @Override
  public void checkRead(String file){
       if(file.endsWith("exe")) {
           throw new AccessControlException("cannot read file:" + file);
       }
       super.checkRead(file);
  }
}

上面的代码将会报错(并且先于判断文件是否存在之前执行):

java.security.AccessControlException: cannot read file:/Users/yulifan/Desktop/ff.exe
  at com.leasehouse.MySecurityManager.checkRead(TestForkJoin.java:30)
  at java.io.FileInputStream.<init>(FileInputStream.java:135)
  at com.leasehouse.TestForkJoin.main(TestForkJoin.java:16)
  at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
  at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
  at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
  at java.lang.reflect.Method.invoke(Method.java:606)
  at com.intellij.rt.execution.application.AppMain.main(AppMain.java:140)