json教程系列（3）-JSONObject的过滤设置

我们通常对一个json串和java对象进行互转时，经常会有选择性的过滤掉一些属性值。例如下面的类：

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public class Person {     private String name;     private String address;     private String sex;       public String getAddress()     {         return address;     }       public void setAddress(String address)     {         this.address = address;     }       public String getName()     {         return name;     }       public void setName(String name)     {         this.name = name;     }       public String getSex()     {         return sex;     }       public void setSex(String sex)     {         this.sex = sex;     } }

如果我想过滤address属性怎么办？

方法一：实现JSONString接口

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import net.sf.json.JSONString; public class Person implements JSONString {     private String name;     private String sex;     private String address;     public String toJSONString()     {         return "{\"name\":\"" + name + "\",\"sex\":\"" + sex + "\"}";     }     public String getAddress()     {         return address;     }     public void setAddress(String address)     {         this.address = address;     }     public String getName()     {         return name;     }     public void setName(String name)     {         this.name = name;     }     public String getSex()     {         return sex;     }     public void setSex(String sex)     {         this.sex = sex;     } } import net.sf.json.JSONObject; public class Test { public static void main(String args[]) {        Person person = new Person();         person.setName("swiftlet");         person.setSex("men");         person.setAddress("china");         JSONObject json = JSONObject.fromObject(person);         System.out.println(json.toString());     } }

方法二：设置jsonconfig实例，对包含和需要排除的属性进行添加或删除。

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import net.sf.json.JSONObject; import net.sf.json.JsonConfig; public class Test {     public static void main(String args[])     {         Person person = new Person();         person.setName("swiftlet");         person.setSex("men");         person.setAddress("china");         JsonConfig jsonConfig = new JsonConfig();         jsonConfig.setExcludes(new String[]         { "address" });         JSONObject json = JSONObject.fromObject(person, jsonConfig);         System.out.println(json.toString());     } }

方法三：使用propertyFilter实例过滤属性。

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import net.sf.json.JSONObject; import net.sf.json.JsonConfig; import net.sf.json.util.PropertyFilter; public class Test {     public static void main(String args[])     {         Person person = new Person();         person.setName("swiftlet");         person.setSex("men");         person.setAddress("china");         JsonConfig jsonConfig = new JsonConfig();         jsonConfig.setJsonPropertyFilter(new PropertyFilter() {             public boolean apply(Object source, String name, Object value)             {                 return source instanceof Person && name.equals("address");             }         });         JSONObject json = JSONObject.fromObject(person, jsonConfig);         System.out.println(json.toString());     } }