<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-databind</artifactId>
<version>2.13.0</version> <!-- 请根据实际情况选择合适的版本 -->
</dependency>
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ObjectMapper类是Jackson库中的主要类，用于在Java对象和JSON数据之间进行转换。以下是ObjectMapper的一些常用使用方法：
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1. 将JSON字符串转换为Java对象：
String jsonString = "{\"name\":\"John\", \"age\":30}";
ObjectMapper mapper = new ObjectMapper();
MyClass obj = mapper.readValue(jsonString, MyClass.class);
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2. 将Java对象转换为JSON字符串：
MyClass obj = new MyClass("John", 30);
ObjectMapper mapper = new ObjectMapper();
String jsonString = mapper.writeValueAsString(obj);
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3. 将JSON数组转换为Java对象数组：
String jsonArrayString = "[{\"name\":\"John\", \"age\":30}, {\"name\":\"Jane\", \"age\":25}]";
ObjectMapper mapper = new ObjectMapper();
MyClass[] objArray = mapper.readValue(jsonArrayString, MyClass[].class);
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4. 将Java对象数组转换为JSON数组：
MyClass[] objArray = new MyClass[]{new MyClass("John", 30), new MyClass("Jane", 25)};
ObjectMapper mapper = new ObjectMapper();
String jsonArrayString = mapper.writeValueAsString(objArray);
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5. 将Java集合转换为JSON字符串：
List<MyClass> objList = new ArrayList<>(Arrays.asList(new MyClass("John", 30), new MyClass("Jane", 25)));
ObjectMapper mapper = new ObjectMapper();
String jsonArrayString = mapper.writeValueAsString(objList);
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6. 将JSON字符串转换为Java Map：
String jsonMapString = "{\"name\":\"John\", \"age\":30}";
ObjectMapper mapper = new ObjectMapper();
Map<String, Object> map = mapper.readValue(jsonMapString, new TypeReference<Map<String, Object>>(){});