ognl总结

 ognl 方法总结

 

// ***************** root对象的概念 ******************* //
public void testOgnl_01() throws Exception{
    User user = new User();
    user.setUsername("张三");

    //相当于调用user.getUsername()方法
    String value = (String)Ognl.getValue("username", user);
    System.out.println(value);
}

public void testOgnl_02() throws Exception{
    User user = new User();
    Person p = new Person();
    p.setName("张三");
    user.setPerson(p);

    //相当于调用user.getPerson().getName()方法
    String value = (String)Ognl.getValue("person.name", user);
    System.out.println(value);
}

public void testOgnl_03() throws Exception{
    User user = new User();
    Person p = new Person();
    p.setName("张三");
    user.setPerson(p);

    //可以使用#root来引用根对象，相当于调用user.getPerson().getName()方法
    String value = (String)Ognl.getValue("#root.person.name", user);
    System.out.println(value);
}

 

 

 

// *********************** context的概念 **********************//
    public void testOgnl_04() throws Exception{
        Person p1 = new Person();
        Person p2 = new Person();
        p1.setName("张三");
        p2.setName("李四");

        Map context = new HashMap();
        context.put("p1", p1);
        context.put("p2", p2);

        String value = (String)Ognl.getValue("#p1.name + ',' + #p2.name", context, new Object());
        System.out.println(value);
    }

    public void testOgnl_05() throws Exception{
        Person p1 = new Person();
        Person p2 = new Person();
        p1.setName("张三");
        p2.setName("李四");

        Map context = new HashMap();
        context.put("p1", p1);
        context.put("p2", p2);

        User root = new User();
        root.setUsername("zhangsan");

        String value = (String)Ognl.getValue("#p1.name + ',' + #p2.name + ',' + username", context, root);
        System.out.println(value);
    }

 

 

 

// ******************* OGNL赋值操作 ************************//
public void testOgnl_06() throws Exception{
    User user = new User();

    //给root对象的属性赋值，相当于调用user.setUsername()
    Ognl.setValue("username", user, "zhangsan");

    System.out.println(user.getUsername());
}

public void testOgnl_07() throws Exception{
    User user = new User();

    Map context = new HashMap();
    context.put("u", user);

    //给context中的对象属性赋值，相当于调用user.setUsername()
    Ognl.setValue("#u.username",context, new Object(), "zhangsan");

    System.out.println(user.getUsername());
}

public void testOgnl_08() throws Exception{
    User user = new User();

    Map context = new HashMap();
    context.put("u", user);

    //给context中的对象属性赋值，相当于调用user.setUsername()
    //在表达式中使用=赋值操作符来赋值
    Ognl.getValue("#u.username = '张三'",context, new Object());

    System.out.println(user.getUsername());
}

public void testOgnl_09() throws Exception{
    User user = new User();
    Person p = new Person();

    Map context = new HashMap();
    context.put("u", user);

    context.put("p", p);

    //给context中的对象属性赋值，相当于调用user.setUsername()
    //在表达式中使用=赋值操作符来赋值
    Ognl.getValue("#u.username = '张三',#p.name = '李四'",context, new Object());

    System.out.println(user.getUsername()+","+p.getName());
}

 

 

 

//****************** 使用OGNL调用对象的方法 **********************//
public void testOgnl_10() throws Exception{
    User user = new User();
    user.setUsername("张三");

    String value = (String)Ognl.getValue("getUsername()", user);
    System.out.println(value);
}

public void testOgnl_11() throws Exception{
    User user = new User();

    Ognl.getValue("setUsername('张三')", user);
    System.out.println(user.getUsername());
}

 

 

 

// ********************* OGNL中的this表达式 **********************//
public void testOgnl_14() throws Exception{
    Object root = new Object();
    Map context = new HashMap();

    List values = new ArrayList();
    for(int i=0; i<11; i++){
        values.add(i);
    }
    context.put("values", values);

    Ognl.getValue("@[e-mail](#values.size.(#this > 10 ? \"大于10\" : '不大于10'))", context, root);

}

public void testOgnl_15() throws Exception{
    User user = new User();

    Ognl.getValue("setUsername('ZHANGSAN')", user);
    Ognl.getValue("@[e-mail](#this.username)", user);
}

public void testOgnl_16() throws Exception{
    User user = new User();

    Ognl.getValue("setUsername('ZHANGSAN')", user);
    Ognl.getValue("@[e-mail](username.(#this.toLowerCase()))", user);
}

 

 

 

// ******************* 如何把表达式的解释结果作为另外一个表达式,OGNL中括号的使用 **********************//
public void testOgnl_17() throws Exception{
    Object root = new Object();
    Map context = new HashMap();
    User u = new User();
    u.setUsername("张三");
    context.put("u", u);
    context.put("fact", "username");

    /**
     * 1、首先把#fact表达式进行解释，得到一个值：username
     * 2、解释括号中的表达式#u，其结果是user对象
     * 3、把括号中表达式的结果作为root对象，解释在第一步中得到的结果（即把第一步的结果看成另外一个表达式）
     */
    String value = (String)Ognl.getValue("#fact(#u)", context, root);
    System.out.println(value);
}

public void testOgnl_18() throws Exception{
    Person person = new Person();
    Map context = new HashMap();
    User u = new User();
    u.setUsername("张三");
    context.put("u", u);

    /**
     * 相当于调用person这个根对象的fact方法，并把#u的解释结果作为参数传入此方法
     */
    String value = (String)Ognl.getValue("fact(#u)", context, person);
    System.out.println(value); //输出是 "张三,"
}

public void testOgnl_19() throws Exception{
    Person person = new Person();
    Map context = new HashMap();
    User u = new User();
    u.setUsername("张三");
    context.put("u", u);

    /**
     * 1、先计算表达式fact，得到结果是：username
     * 2、解释括号中的表达式#u，其结果是user对象
     * 3、把括号中表达式的结果作为root对象，解释在第一步中得到的结果（即把第一步的结果看成另外一个表达式）
     */
    String value = (String)Ognl.getValue("(fact)(#u)", context, person);
    System.out.println(value); //输出"张三"
}

 

 

 

 

 

// ********************* OGNL访问集合元素 **************************//
public void testOgnl_20() throws Exception{
    Object root = new Object();
    Map context = new HashMap();

    //用OGNL创建List对象
    List listvalue = (List)Ognl.getValue("{123,'kdjfk','oooo'}", context, root);
    context.put("listvalue", listvalue);

    //用OGNL创建数组
    int[] intarray= (int[])Ognl.getValue("new int[]{23,45,67}", context, root);
    context.put("intarray", intarray);

    //用OGNL创建Map对象
    Map mapvalue = (Map)Ognl.getValue("#{'listvalue':#listvalue,'intarray':#intarray}", context, root);
    context.put("mapvalue", mapvalue);

    Ognl.getValue("@[e-mail](#listvalue[0])", context, root);
    Ognl.getValue("@[e-mail](#intarray[1])", context, root);
    Ognl.getValue("@[e-mail](#mapvalue['intarray'][2])", context, root);
    Ognl.getValue("@[e-mail](#mapvalue.intarray[0])", context, root);
}