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：

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 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

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 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。

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 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。

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 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 ( ) ) ;      } }