Jackson解析json字符串问题记录

今天做一个简单的http的post提交，用@RequestBody来解析json参数，转为一个对象，发现对象属性如果是cName，这样的单字母小写开头+大写字母为第二个的属性，会有一个小问题，下面做个小demo记录下。

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1.我们有个数据库表stu，字段分别是name,c_name,cc_name，按照正常的驼峰规则生成实体类

public class Stu {
    private String name;
    private String cName;
    private String ccName;

    public String getName() {
        return name;
    }

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

    public String getCName() {
        return cName;
    }

    public void setCName(String cName) {
        this.cName = cName;
    }

    public String getCcName() {
        return ccName;
    }

    public void setCcName(String ccName) {
        this.ccName = ccName;
    }
}

2.增加Main方法测试下Jackson的json转对象

public static void main(String[] args) {
        String json = "{\"name\":\"name\",\"cName\":\"cName\",\"ccName\":\"ccName\"}";
        ObjectMapper mapper = new ObjectMapper();
        mapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);

        try {
            Stu s = mapper.readValue(json, Stu.class);
            System.out.println("name:" + s.getName());
            System.out.println("cName:" + s.getCName());
            System.out.println("ccName:" + s.getCcName());
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

3.结果是什么？按照我们的一贯想法结果肯定是
name:name
cName:cName
ccName:ccName
但是真实结果却是

4.然后我们改一下cName的set方法，改为public setcName

public class Stu {
    private String name;
    private String cName;
    private String ccName;

    public String getName() {
        return name;
    }

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

    public String getCName() {
        return cName;
    }

    public void setcName(String cName) {
        this.cName = cName;
    }

    public String getCcName() {
        return ccName;
    }

    public void setCcName(String ccName) {
        this.ccName = ccName;
    }

结果变成了我们想要的

5.当然也可以用注解JsonProperty解决

public class Stu {
    private String name;
    @JsonProperty("cName")
    private String cName;
    private String ccName;

    public String getName() {
        return name;
    }

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

    public String getCName() {
        return cName;
    }

    public void setCName(String cName) {
        this.cName = cName;
    }

    public String getCcName() {
        return ccName;
    }

    public void setCcName(String ccName) {
        this.ccName = ccName;
    }

    public static void main(String[] args) {
        String json = "{\"name\":\"name\",\"cName\":\"cName\",\"ccName\":\"ccName\"}";
        ObjectMapper mapper = new ObjectMapper();
        mapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);

        try {
            Stu s = mapper.readValue(json, Stu.class);
            System.out.println("name:" + s.getName());
            System.out.println("cName:" + s.getCName());
            System.out.println("ccName:" + s.getCcName());
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

结果和预想结果一样

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这个原因还没有查到，百度不到类似情况，先记录下。