Java JSON处理：解析与生成示例

原创小灰灰 2024-11-09 17:48 132阅读 0赞

在Java中处理JSON数据，常用的库有`Jackson`和`Gson`。下面我将分别提供使用这两个库进行JSON解析和生成的示例。

### 使用Jackson库#### 添加依赖首先，确保你的项目中添加了Jackson的依赖。如果你使用Maven，可以在`pom.xml`文件中添加以下依赖：

```xml<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-databind</artifactId>
<version>2.13.0</version>
</dependency>
```#### 解析JSON```javaimport com.fasterxml.jackson.databind.ObjectMapper;

public class JacksonExample {
 public static void main(String[] args) {
String json = "{\"name\":\"John\", \"age\":30}";
 ObjectMapper mapper = new ObjectMapper();

try {
 Person person = mapper.readValue(json, Person.class);
 System.out.println("Name: " + person.getName());
 System.out.println("Age: " + person.getAge());
} catch (Exception e) {
e.printStackTrace();
 }
 }

static class Person {
 private String name;
 private int age;

// getters and setters public String getName() {
 return name;
 }

public void setName(String name) {
 this.name = name;
 }

public int getAge() {
 return age;
 }

public void setAge(int age) {
 this.age = age;
 }
 }
}
```#### 生成JSON```javaimport com.fasterxml.jackson.databind.ObjectMapper;

public class JacksonGenerateExample {
 public static void main(String[] args) {
 Person person = new Person();
 person.setName("John");
 person.setAge(30);

ObjectMapper mapper = new ObjectMapper();

try {
String json = mapper.writeValueAsString(person);
 System.out.println(json);
} catch (Exception e) {
e.printStackTrace();
 }
 }

static class Person {
 private String name;
 private int age;

// getters and setters public String getName() {
 return name;
 }

public void setName(String name) {
 this.name = name;
 }

public int getAge() {
 return age;
 }

public void setAge(int age) {
 this.age = age;
 }
 }
}
```### 使用Gson库#### 添加依赖如果你使用Maven，可以在`pom.xml`文件中添加以下依赖：

```xml<dependency>
<groupId>com.google.code.gson</groupId>
<artifactId>gson</artifactId>
<version>2.8.8</version>
</dependency>
```#### 解析JSON```javaimport com.google.gson.Gson;

public class GsonExample {
 public static void main(String[] args) {
String json = "{\"name\":\"John\", \"age\":30}";
 Gson gson = new Gson();

Person person = gson.fromJson(json, Person.class);
 System.out.println("Name: " + person.getName());
 System.out.println("Age: " + person.getAge());
 }

static class Person {
 private String name;
 private int age;

// getters and setters public String getName() {
 return name;
 }

public void setName(String name) {
 this.name = name;
 }

public int getAge() {
 return age;
 }

public void setAge(int age) {
 this.age = age;
 }
 }
}
```#### 生成JSON```javaimport com.google.gson.Gson;

public class GsonGenerateExample {
 public static void main(String[] args) {
 Person person = new Person();
 person.setName("John");
 person.setAge(30);

Gson gson = new Gson();
String json = gson.toJson(person);
 System.out.println(json);
 }

static class Person {
 private String name;
 private int age;

// getters and setters public String getName() {
 return name;
 }

public void setName(String name) {
 this.name = name;
 }

public int getAge() {
 return age;
 }

public void setAge(int age) {
 this.age = age;
 }
 }
}
```这些示例展示了如何使用Jackson和Gson库在Java中解析和生成JSON数据。你可以根据需要选择使用其中一个库。