From bc2c1ccc6efe1300ff26b6aa7bd4caf737e2b027 Mon Sep 17 00:00:00 2001 From: Calvin Date: Sat, 28 Apr 2012 01:52:06 +0800 Subject: [PATCH] =?UTF-8?q?jackson=20=E6=96=87=E6=A1=A3=E5=B9=B6=E6=95=B4?= =?UTF-8?q?=E7=90=86=E4=BB=A3=E7=A0=81.?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- .../common/service/AccountManager.java | 6 +- .../showcase/utilities/json/JsonDemo.java | 135 +++++++++--------- .../springside/modules/mapper/JsonMapper.java | 25 ++-- .../modules/mapper/JsonMapperTest.java | 6 +- 4 files changed, 80 insertions(+), 92 deletions(-) diff --git a/examples/showcase/src/main/java/org/springside/examples/showcase/common/service/AccountManager.java b/examples/showcase/src/main/java/org/springside/examples/showcase/common/service/AccountManager.java index 7027bff2..dd3b065d 100644 --- a/examples/showcase/src/main/java/org/springside/examples/showcase/common/service/AccountManager.java +++ b/examples/showcase/src/main/java/org/springside/examples/showcase/common/service/AccountManager.java @@ -38,7 +38,7 @@ public class AccountManager { private SpyMemcachedClient memcachedClient; - private JsonMapper jsonBinder = JsonMapper.buildNonDefaultMapper(); + private JsonMapper jsonMapper = JsonMapper.nonDefaultMapper(); private NotifyMessageProducer notifyProducer; //JMS消息发送 @@ -134,11 +134,11 @@ public class AccountManager { //因为hibernate的proxy在序列化时问题多多,此处使用jdbc user = userMyBatisDao.getUser(id); if (user != null) { - jsonString = jsonBinder.toJson(user); + jsonString = jsonMapper.toJson(user); memcachedClient.set(key, MemcachedObjectType.USER.getExpiredTime(), jsonString); } } else { - user = jsonBinder.fromJson(jsonString, User.class); + user = jsonMapper.fromJson(jsonString, User.class); } return user; } diff --git a/examples/showcase/src/main/java/org/springside/examples/showcase/utilities/json/JsonDemo.java b/examples/showcase/src/main/java/org/springside/examples/showcase/utilities/json/JsonDemo.java index 8ba8f0dc..f7abcfef 100644 --- a/examples/showcase/src/main/java/org/springside/examples/showcase/utilities/json/JsonDemo.java +++ b/examples/showcase/src/main/java/org/springside/examples/showcase/utilities/json/JsonDemo.java @@ -47,7 +47,7 @@ import com.google.common.collect.Maps; */ public class JsonDemo { - private static JsonMapper mapper = JsonMapper.buildNonDefaultMapper(); + private static JsonMapper mapper = JsonMapper.nonDefaultMapper(); //// 基本操作 演示 //// @@ -126,10 +126,10 @@ public class JsonDemo { } /** - * 测试三种不同的Binder. + * 测试三种不同的Inclusion风格. */ @Test - public void threeTypeBinders() { + public void threeTypeInclusion() { TestBean bean = new TestBean("A"); //打印全部属性 @@ -137,11 +137,11 @@ public class JsonDemo { assertEquals("{\"name\":\"A\",\"defaultValue\":\"hello\",\"nullValue\":null}", normalMapper.toJson(bean)); //不打印nullValue属性 - JsonMapper nonNullMapper = JsonMapper.buildNonNullMapper(); + JsonMapper nonNullMapper = JsonMapper.nonEmptyMapper(); assertEquals("{\"name\":\"A\",\"defaultValue\":\"hello\"}", nonNullMapper.toJson(bean)); //不打印默认值未改变的nullValue与defaultValue属性 - JsonMapper nonDefaultMaper = JsonMapper.buildNonDefaultMapper(); + JsonMapper nonDefaultMaper = JsonMapper.nonDefaultMapper(); assertEquals("{\"name\":\"A\"}", nonDefaultMaper.toJson(bean)); } @@ -180,17 +180,7 @@ public class JsonDemo { } /** - * 測試輸出jsonp格式內容. - */ - @Test - public void jsonp() { - TestBean bean = new TestBean("foo"); - String jsonpString = mapper.toJsonP("callback", bean); - assertEquals("callback({\"name\":\"foo\"})", jsonpString); - } - - /** - * JSON字符串裡只含有Bean中部分的屬性時，更新一個已存在Bean，只覆蓋部分的屬性. + * 更新一個已存在Bean，JSON字符串裡只含有Bean的部分屬性，只覆蓋这部分的屬性. */ @Test public void updateBean() { @@ -198,13 +188,25 @@ public class JsonDemo { TestBean bean = new TestBean(); bean.setDefaultValue("Foobar"); + bean = mapper.update(jsonString, bean); + //name被赋值 assertEquals("A", bean.getName()); //DefaultValue不在Json串中，依然保留。 assertEquals("Foobar", bean.getDefaultValue()); } + /** + * 測試輸出jsonp格式內容. + */ + @Test + public void jsonp() { + TestBean bean = new TestBean("foo"); + String jsonpString = mapper.toJsonP("callback", bean); + assertEquals("callback({\"name\":\"foo\"})", jsonpString); + } + /** * 演示用的Bean, 主要演示不同風格的Mapper對Null值，初始化後沒改變過的屬性值的處理. */ @@ -254,17 +256,18 @@ public class JsonDemo { ////特殊数据类型演示//// /** - * 测试对枚举的序列化,可以選擇用一個int字段(但不是order)而不是以Name來序列化，以減少長度. + * 测试对枚举的序列化. */ @Test - public void enumData() { - //默認使用enum.name() + public void enumType() { + //toJSon默認使用enum.name() assertEquals("\"One\"", mapper.toJson(TestEnum.One)); + //fromJson使用enum.name()或enum.order() assertEquals(TestEnum.One, mapper.fromJson("\"One\"", TestEnum.class)); + assertEquals(TestEnum.One, mapper.fromJson("0", TestEnum.class)); - //使用enum.toString() - //注意，index會通過toString序列成字符串而不是int,否則会和order()順序號混淆. - //注意配置必須在所有讀寫動作之前調用. + //使用enum.toString(), 注意配置必須在所有讀寫動作之前調用. + //建议toString()使用index数字属性，比enum.name()节约了空间，比enum.order()则不会有顺序随时改变不确定的问题。 JsonMapper newMapper = new JsonMapper(); newMapper.enableEnumUseToString(); assertEquals("\"1\"", newMapper.toJson(TestEnum.One)); @@ -290,16 +293,17 @@ public class JsonDemo { } /** - * 测试对日期的序列化,日期默认以Timestamp方式存储，也可以用@JsonFormat格式化. + * 测试对日期的序列化,日期默认以Timestamp方式存储，也可以用2.0后也可以用@JsonFormat在属性上格式化. */ @Test - public void dateData() { - DateBean dateBean = new DateBean(); + public void dateType() { + Date date = new Date(); String timestampString = String.valueOf(date.getTime()); String format = "yyyy-MM-dd HH:mm:ss"; String formatedString = new DateTime(date).toString(format); + DateBean dateBean = new DateBean(); dateBean.startDate = date; dateBean.endDate = date; @@ -317,8 +321,9 @@ public class JsonDemo { } public static class DateBean { - + //默认timestamp存储 public Date startDate; + //按annotation中的日期格式存储。 @JsonFormat(pattern = "yyyy-MM-dd HH:mm:ss", timezone = "GMT+08:00") public Date endDate; @@ -366,15 +371,15 @@ public class JsonDemo { * 測試父子POJO間的循環引用. */ @Test - public void parentChildBean() { + public void cycleReferenceBean() { //初始化对象关系，parent的children里含有 child1,child2, child1/child2的parent均指向parent. - ParentChildBean parent = new ParentChildBean("parent"); + CycleReferenceBean parent = new CycleReferenceBean("parent"); - ParentChildBean child1 = new ParentChildBean("child1"); + CycleReferenceBean child1 = new CycleReferenceBean("child1"); child1.setParent(parent); parent.getChildren().add(child1); - ParentChildBean child2 = new ParentChildBean("child2"); + CycleReferenceBean child2 = new CycleReferenceBean("child2"); child2.setParent(parent); parent.getChildren().add(child2); @@ -386,11 +391,11 @@ public class JsonDemo { assertEquals("{\"name\":\"child1\"}", mapper.toJson(child1)); //反向序列化时，Json已很聪明的把parent填入child1/child2中. - ParentChildBean parentResult = mapper.fromJson(jsonString, ParentChildBean.class); + CycleReferenceBean parentResult = mapper.fromJson(jsonString, CycleReferenceBean.class); assertEquals("parent", parentResult.getChildren().get(0).getParent().getName()); //单独反序列化child1，当然parent也是空 - ParentChildBean child1Result = mapper.fromJson("{\"name\":\"child1\"}", ParentChildBean.class); + CycleReferenceBean child1Result = mapper.fromJson("{\"name\":\"child1\"}", CycleReferenceBean.class); assertNull(child1Result.parent); assertEquals("child1", child1Result.getName()); } @@ -398,16 +403,16 @@ public class JsonDemo { /** * 父子POJO間的循環引用的演示Bean,@JsonBackReference 与 @JsonManagedReference 是关键. */ - public static class ParentChildBean { + public static class CycleReferenceBean { private String name; - private ParentChildBean parent; - private List children = Lists.newArrayList(); + private CycleReferenceBean parent; + private List children = Lists.newArrayList(); - public ParentChildBean() { + public CycleReferenceBean() { } - public ParentChildBean(String name) { + public CycleReferenceBean(String name) { this.name = name; } @@ -421,28 +426,31 @@ public class JsonDemo { //注意getter與setter都要添加annotation @JsonBackReference - public ParentChildBean getParent() { + public CycleReferenceBean getParent() { return parent; } @JsonBackReference - public void setParent(ParentChildBean parent) { + public void setParent(CycleReferenceBean parent) { this.parent = parent; } @JsonManagedReference - public List getChildren() { + public List getChildren() { return children; } @JsonManagedReference - public void setChildren(List children) { + public void setChildren(List children) { this.children = children; } } /** - * 測試可擴展Bean,會自動的把確定的屬性放入固定的成員變量, 其他屬性放到一个类型为Map的成员变量裡,能很好的支持Bean版本升级时固定属性的变动. + * 測試可擴展Bean. + * 可扩展Bean的设计会混合一些的固定属性和用一个Map存放的扩展属性。 + * 通常，哪那些是固定属性，哪些是扩展属性，在应用不断演进中是不断变化的。 + * Jackson支持将所有属性都序列化成平行的属性列表，没有固定属性与Map中属性的区别，然后智能的将不在固定列的属性都丢到被@JsonAnyGetter/Setter注释的Map里面去。 */ @Test public void extensibleBean() { @@ -489,23 +497,22 @@ public class JsonDemo { } /** - * 測試序列化Bean时使用不同的View序列化不同的属性组, 及@JsonIgnore標註的屬性. + * 同一种POJO，在不同场景下可能需要序列化不同的属性组，Jackson支持使用View来定义. */ @Test - public void viewBean() throws IOException { - ViewBean viewBean = new ViewBean(); - viewBean.setName("Foo"); - viewBean.setAge(16); - viewBean.setOtherValue("others"); - viewBean.setIgnoreValue("ignored"); + public void multiViewBean() throws IOException { + MultiViewBean multiViewBean = new MultiViewBean(); + multiViewBean.setName("Foo"); + multiViewBean.setAge(16); + multiViewBean.setOtherValue("others"); //public view ObjectWriter publicWriter = mapper.getMapper().writerWithView(Views.Public.class); - assertEquals("{\"name\":\"Foo\",\"otherValue\":\"others\"}", publicWriter.writeValueAsString(viewBean)); + assertEquals("{\"name\":\"Foo\",\"otherValue\":\"others\"}", publicWriter.writeValueAsString(multiViewBean)); //internal view ObjectWriter internalWriter = mapper.getMapper().writerWithView(Views.Internal.class); - assertEquals("{\"age\":16,\"otherValue\":\"others\"}", internalWriter.writeValueAsString(viewBean)); + assertEquals("{\"age\":16,\"otherValue\":\"others\"}", internalWriter.writeValueAsString(multiViewBean)); } @@ -520,11 +527,10 @@ public class JsonDemo { /** * 演示序列化不同View不同属性的Bean. */ - public static class ViewBean { + public static class MultiViewBean { private String name; private int age; private String otherValue; - private String ignoreValue; @JsonView(Views.Public.class) public String getName() { @@ -551,27 +557,17 @@ public class JsonDemo { public void setOtherValue(String otherValue) { this.otherValue = otherValue; } - - @JsonIgnore - public String getIgnoreValue() { - return ignoreValue; - } - - public void setIgnoreValue(String ignoreValue) { - this.ignoreValue = ignoreValue; - } - } - ////批量定制行为//// + ////自定制行为//// /** - * 测试 自定义转换器，整体感觉稍显复杂。目标是将Money和Long互转. + * 测试自定义转换器，整体感觉稍显复杂。这里是将Money和Long互转. */ @Test public void customConverter() { - JsonMapper newMapper = JsonMapper.buildNonNullMapper(); + JsonMapper newMapper = JsonMapper.nonEmptyMapper(); SimpleModule moneyModule = new SimpleModule("MoneyModule"); moneyModule.addSerializer(new MoneySerializer()); @@ -663,14 +659,14 @@ public class JsonDemo { } /** - * 测试修改 属性名策略 + * 测试修改 属性名策略。 */ @Test public void customPropertyNaming() throws JsonMappingException { TestBean bean = new TestBean("foo"); bean.setDefaultValue("bar"); - JsonMapper newMapper = JsonMapper.buildNonNullMapper(); + JsonMapper newMapper = JsonMapper.nonEmptyMapper(); newMapper.getMapper().setPropertyNamingStrategy(new LowerCaseNaming()); String jsonpString = newMapper.toJson(bean); assertEquals("{\"name\":\"foo\",\"defaultvalue\":\"bar\"}", jsonpString); @@ -682,5 +678,4 @@ public class JsonDemo { return defaultName.toLowerCase(); } } - -} +} \ No newline at end of file diff --git a/modules/core/src/main/java/org/springside/modules/mapper/JsonMapper.java b/modules/core/src/main/java/org/springside/modules/mapper/JsonMapper.java index ca861ebf..cdef7da1 100644 --- a/modules/core/src/main/java/org/springside/modules/mapper/JsonMapper.java +++ b/modules/core/src/main/java/org/springside/modules/mapper/JsonMapper.java @@ -45,26 +45,19 @@ public class JsonMapper { } /** - * 创建只输出非空属性到Json字符串的Mapper. + * 创建只输出非Null且非Empty(如List.isEmpty)的属性到Json字符串的Mapper,建议在外部接口中使用. */ - public static JsonMapper buildNonNullMapper() { - return new JsonMapper(Include.NON_NULL); - } - - /** - * 创建只输出初始值被改变的属性到Json字符串的Mapper. - */ - public static JsonMapper buildNonDefaultMapper() { - return new JsonMapper(Include.NON_DEFAULT); - } - - /** - * 创建只输出非Null且非Empty(如List.isEmpty)的属性到Json字符串的Mapper. - */ - public static JsonMapper buildNonEmptyMapper() { + public static JsonMapper nonEmptyMapper() { return new JsonMapper(Include.NON_EMPTY); } + /** + * 创建只输出初始值被改变的属性到Json字符串的Mapper, 最节约的存储方式，建议在内部接口中使用。 + */ + public static JsonMapper nonDefaultMapper() { + return new JsonMapper(Include.NON_DEFAULT); + } + /** * Object可以是POJO，也可以是Collection或数组。 * 如果对象为Null, 返回"null". diff --git a/modules/core/src/test/java/org/springside/modules/mapper/JsonMapperTest.java b/modules/core/src/test/java/org/springside/modules/mapper/JsonMapperTest.java index 0e97d6dc..81d5173f 100644 --- a/modules/core/src/test/java/org/springside/modules/mapper/JsonMapperTest.java +++ b/modules/core/src/test/java/org/springside/modules/mapper/JsonMapperTest.java @@ -21,7 +21,7 @@ import com.google.common.collect.Maps; */ public class JsonMapperTest { - private static JsonMapper binder = JsonMapper.buildNonDefaultMapper(); + private static JsonMapper binder = JsonMapper.nonDefaultMapper(); /** * 序列化对象/集合到Json字符串. @@ -145,11 +145,11 @@ public class JsonMapperTest { assertEquals("{\"name\":\"A\",\"defaultValue\":\"hello\",\"nullValue\":null}", normalBinder.toJson(bean)); //不打印nullValue属性 - JsonMapper nonNullBinder = JsonMapper.buildNonNullMapper(); + JsonMapper nonNullBinder = JsonMapper.nonEmptyMapper(); assertEquals("{\"name\":\"A\",\"defaultValue\":\"hello\"}", nonNullBinder.toJson(bean)); //不打印默认值未改变的nullValue与defaultValue属性 - JsonMapper nonDefaultBinder = JsonMapper.buildNonDefaultMapper(); + JsonMapper nonDefaultBinder = JsonMapper.nonDefaultMapper(); assertEquals("{\"name\":\"A\"}", nonDefaultBinder.toJson(bean)); }