ognl

来源：互联网发布：编程需要学的软件编辑：程序博客网时间：2024/04/28 05:03

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import ognl.Ognl;
import ognl.OgnlContext;
import ognl.OgnlException;

public class OgnlTest {
   public static void main(String[] args) {
       Persion persion = new Persion();
       Dog dog = new Dog();
       persion.setName("ZhuGouLiang");
       dog.setName("WangCai");
       OgnlContext context = new OgnlContext();
       context.put("persion", persion);
       context.put("dog", dog);
       context.setRoot(persion);

       getOgnlValue(context, "name");
       getOgnlValue(context, "#persion.name");
       getOgnlValue(context, "#dog.name");
       getOgnlValue(context, "name.toUpperCase()");
       getOgnlValue(context, "#persion.name");
       // 调用静态方法
       getOgnlValue(context, "@java.lang.Integer@toBinaryString(10)");
       // Ognl的默认class是Math
       getOgnlValue(context, "@@min(10,5)");
       // Ognl访问静态的属性
       getOgnlValue(context, "@@PI");

       getOgnlValue(context, "new java.util.ArrayList()");
       // 数组和集合对象是一样的，都是通过索引下标得到value
       getOgnlValue(context, "{'aa','bb','cc','dd'}");
       getOgnlValue(context, "{'aa','bb','cc','dd'}[2]");

       dog.setFriends(new String[] { "aa", "bb", "cc", "dd" });
       getOgnlValue(context, "#dog.friends");
       getOgnlValue(context, "#dog.friends[0]");
       // 集合伪属性 ---size isEmpty
       // 集合--list
       List<String> list = new ArrayList<String>();
       list.add("chenyanshan");
       list.add("liuyoujuan");
       list.add("chuanzhiboke");
       context.put("list", list);
       getOgnlValue(context, "#list[0]");
       // 集合--map
       Map<String, String> map = new HashMap<String, String>();
       map.put("me", "chenyanshan");
       map.put("she", "liuyoujuan");
       map.put("other", ".....");
       context.put("map", map);
       getOgnlValue(context, "#map['me']");

       getOgnlValue(context,
               "#{'me':'chenyanshan','she':'liuyoujuan','other':'.....'}['me']");

       // filter---collection.{? expression}
       List<Persion> persions = new ArrayList<Persion>();
       Persion ps1 = new Persion();
       Persion ps2 = new Persion();
       Persion ps3 = new Persion();
       ps1.setName("chenyanshan");
       ps2.setName("liuyoujuan");
       ps3.setName("other");
       persions.add(ps1);
       persions.add(ps2);
       persions.add(ps3);
       context.put("persions", persions);
       getOgnlValue(context, "#persions.{? #this.name.length() > 6}.size()");

       // filter 获取集合的第一个元素---collection.{^ expression}
       getOgnlValue(context, "#persions.{^ #this.name.length() > 6}[0].name");

       // filter 获取集合的最后一个元素---collection.{^ expression}
       getOgnlValue(context, "#persions.{$ #this.name.length() > 6}[0].name");

       // 投影(projection)---collection.{expression}
       getOgnlValue(context, "#persions.{name}");
       getOgnlValue(context, "#persions.{#this.name.length()<=6 ? 'hello world' : #this.name}");

   }

   private static void getOgnlValue(OgnlContext context, String valueFromString) {
       Object obj_class;
       try {
           obj_class = Ognl.parseExpression(valueFromString);
           System.out.println(obj_class);
           Object obj_value = Ognl.getValue(obj_class, context,
                   context.getRoot());
           System.out.println(obj_value);
           System.out.println("-------------");

       } catch (OgnlException e) {
           e.printStackTrace();
       }
   }
}

public class Dog {
   private String name;

   private String[] friends;

   public String getName() {
       return name;
   }

   public void setName(String name) {
       this.name = name;
   }

   public String[] getFriends() {
       return friends;
   }

   public void setFriends(String[] friends) {
       this.friends = friends;
   }
}

public class Persion {
   private String name;

   public String getName() {
       return name;
   }

   public void setName(String name) {
       this.name = name;
   }
}

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