1. 传入一个object类型的对象
2. 获取该对象的class类
3. getFields方法获取该类的所有属性
4. 对属性进行遍历，并且拼接成Json格式的字符串，注意：通过属性名来推断方法名
5. 获取Method实例
6. 通过invoke方法调用

public static String objectToJsonUtil(Object object) throws Exception {String s = "{";Class c = object.getClass();Field[] fields = c.getFields();for(Field f : fields){String name = "get"+String.valueOf(f.getName().charAt(0)).toUpperCase()+f.getName().substring(1);Method method = c.getMethod(name);s+=f.getName()+":"+method.invoke(object)+",";}s=s.substring(0,s.length()-1);s+="}";return s;}

以User类进行测试

public class User {private int id;private String name;public User(int id, String name) {this.id = id;this.name = name;}public User(){}public String getName() {return name;}public void setName(String name) {this.name = name;}public int getId() {return id;}public void setId(int id) {this.id = id;}@Overridepublic String toString() {return "User{" +"name='" + name + '\'' +", id=" + id +'}';}
}

User user = new User(1,"tom");
String s = objectToJson(user);
System.out.println(s);