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创建项目并导包

创建一个User类

package cn.itheima.bean;public class User {
   	private String name;	private Integer age;		public User() {
   		super();	}	public User(String name, Integer age) {
   		super();		this.name = name;		this.age = age;	}	public String getName() {
   		return name;	}	public void setName(String name) {
   		this.name = name;	}	public Integer getAge() {
   		return age;	}	public void setAge(Integer age) {
   		this.age = age;	}	@Override	public String toString() {
   		return "User [name=" + name + ", age=" + age + "]";	}}

准备工作

@Test//准备工作public void fun1() throws Exception{
   	//准备ONGLContext		//准备Root		User rootUser = new User("tom",18);		//准备Context		Map
   
     context = new HashMap
    
     ();		context.put("user1", new User("jack",18));		context.put("user2", new User("rose",22));	OgnlContext oc = new OgnlContext();	//将rootUser作为root部分	oc.setRoot(rootUser);	//将context这个Map作为Context部分	oc.setValues(context);	//书写OGNL	Ognl.getValue("", oc, oc.getRoot());}
    
   

取root中的属性值

@Test//取出root中的属性值public void fun2() throws Exception{
   	//准备ONGLContext		//准备Root		User rootUser = new User("tom",18);		//准备Context		Map
   
     context = new HashMap
    
     ();		context.put("user1", new User("jack",18));		context.put("user2", new User("rose",22));	OgnlContext oc = new OgnlContext();	oc.setRoot(rootUser);	oc.setValues(context);	//书写OGNL		//取出root中user对象的name属性	String name = (String) Ognl.getValue("name", oc, oc.getRoot());	Integer age = (Integer) Ognl.getValue("age", oc, oc.getRoot());	System.out.println(name);	System.out.println(age);}
    
   

运行Junit测试，控制台打印：

tom18

取出context中的属性值

public void fun3() throws Exception{
   	//准备ONGLContext		//准备Root		User rootUser = new User("tom",18);		//准备Context		Map
   
     context = new HashMap
    
     ();		context.put("user1", new User("jack",18));		context.put("user2", new User("rose",22));	OgnlContext oc = new OgnlContext();	oc.setRoot(rootUser);	oc.setValues(context);	//书写OGNL		//取出context中键为user1对象的name属性	String name = (String) Ognl.getValue("#user1.name", oc, oc.getRoot());	String name2 = (String) Ognl.getValue("#user2.name", oc, oc.getRoot());	Integer age = (Integer) Ognl.getValue("#user2.age", oc, oc.getRoot());	System.out.println(name);	System.out.println(name2);	System.out.println(age);}
    
   

运行Junit测试，控制台打印：

jackrose22

为属性赋值

@Test//基本语法演示//为属性赋值public void fun4() throws Exception{
   	//准备ONGLContext		//准备Root		User rootUser = new User("tom",18);		//准备Context		Map
   
     context = new HashMap
    
     ();		context.put("user1", new User("jack",18));		context.put("user2", new User("rose",22));	OgnlContext oc = new OgnlContext();	oc.setRoot(rootUser);	oc.setValues(context);	//书写OGNL		//将root中的user对象的name属性赋值	Ognl.getValue("name='jerry'", oc, oc.getRoot());	String name = (String) Ognl.getValue("name", oc, oc.getRoot());	//将Context中的user对象的name属性赋值  	//可以使用（,）将表达式进行串联执行，但是多个表达式串联，如果有多个返回值，只返回最后一个表达式的	String name2 = (String) Ognl.getValue("#user1.name='二狗', #user1.name", oc, oc.getRoot());	System.out.println(name);	System.out.println(name2);}
    
   

运行Junit测试，控制台打印：

jerry二狗

调用方法

@Test//调用方法public void fun5() throws Exception{
   	//准备ONGLContext		//准备Root		User rootUser = new User("tom",18);		//准备Context		Map
   
     context = new HashMap
    
     ();		context.put("user1", new User("jack",18));		context.put("user2", new User("rose",22));	OgnlContext oc = new OgnlContext();	oc.setRoot(rootUser);	oc.setValues(context);	//书写OGNL		//调用root中user对象的setName方法	Ognl.getValue("setName('lilei')", oc, oc.getRoot());	String name = (String) Ognl.getValue("getName()", oc, oc.getRoot());	//调用context中user对象的setName方法	String name2 = (String) Ognl.getValue("#user1.setName('lucy'),#user1.getName()", oc, oc.getRoot());			System.out.println(name);	System.out.println(name2);}
    
   

运行Junit测试，控制台打印：

lileilucy

调用静态方法

创建一个工具类，定义一个静态方法：

package pers.zhang.Utils;public class HahaUtils {
   		//回音方法	public static Object echo(Object o){
   		return o;	}}

@Test//基本语法演示//调用静态方法public void fun6() throws Exception{
   	//准备ONGLContext		//准备Root		User rootUser = new User("tom",18);		//准备Context		Map
   
     context = new HashMap
    
     ();		context.put("user1", new User("jack",18));		context.put("user2", new User("rose",22));	OgnlContext oc = new OgnlContext();	oc.setRoot(rootUser);	oc.setValues(context);	//书写OGNL	//@+完整类名+@+方法	String name = (String) Ognl.getValue("@pers.zhang.Utils@echo('hello 强勇!')", oc, oc.getRoot());	//Double pi = (Double) Ognl.getValue("@java.lang.Math@PI", oc, oc.getRoot());	//访问Math的简写	Double pi = (Double) Ognl.getValue("@@PI", oc, oc.getRoot());	System.out.println(name);	System.out.println(pi);}
    
   

运行Junit测试，控制台打印：

hello 二狗3.141592653589793

ognl创建对象（List，Map）

@Test//基本语法演示//ognl创建对象-list|mappublic void fun7() throws Exception{
   	//准备ONGLContext		//准备Root		User rootUser = new User("tom",18);		//准备Context		Map
   
     context = new HashMap
    
     ();		context.put("user1", new User("jack",18));		context.put("user2", new User("rose",22));	OgnlContext oc = new OgnlContext();	oc.setRoot(rootUser);	oc.setValues(context);	//书写OGNL		//创建list对象	Integer size = (Integer) Ognl.getValue("{'tom','jerry','jack','rose'}.size()", oc, oc.getRoot());	String name = (String) Ognl.getValue("{'tom','jerry','jack','rose'}[0]", oc, oc.getRoot());	String name2 = (String) Ognl.getValue("{'tom','jerry','jack','rose'}.get(1)", oc, oc.getRoot());	/*System.out.println(size);	System.out.println(name);	System.out.println(name2);*/	//创建Map对象	Integer size2 = (Integer) Ognl.getValue("#{'name':'tom','age':18}.size()", oc, oc.getRoot());	String name3  = (String) Ognl.getValue("#{'name':'tom','age':18}['name']", oc, oc.getRoot());	Integer age  = (Integer) Ognl.getValue("#{'name':'tom','age':18}.get('age')", oc, oc.getRoot());	System.out.println(size2);	System.out.println(name3);	System.out.println(age);}
    
   

运行Junit测试，控制台输出：

2tom18

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