Java中@Accessors注解的具体使用

import lombok.AccessLevel;
import lombok.Setter;
import lombok.ToString;
import lombok.experimental.Accessors;

@ToString
@Accessors(chain = true, fluent = true)
public class Example {
    @Setter(AccessLevel.PROTECTED)
    private String name;

    private int age;
}

/**
 * A container for settings for the generation of getters and setters.
 * <p>
 * Complete documentation is found at <a href="https://projectlombok.org/features/experimental/Accessors" rel="external nofollow" >the project lombok features page for &#64;Accessors</a>.
 * <p>
 * Using this annotation does nothing by itself; an annotation that makes lombok generate getters and setters,
 * such as {@link lombok.Setter} or {@link lombok.Data} is also required.
 */
@Target({ElementType.TYPE, ElementType.FIELD})
@Retention(RetentionPolicy.SOURCE)
public @interface Accessors {
	/**
	 * If true, accessors will be named after the field and not include a {@code get} or {@code set}
	 * prefix. If true and {@code chain} is omitted, {@code chain} defaults to {@code true}.
	 * <strong>default: false</strong>
	 * 
	 * @return Whether or not to make fluent methods (named {@code fieldName()}, not for example {@code setFieldName}).
	 */
	boolean fluent() default false;
	
	/**
	 * If true, setters return {@code this} instead of {@code void}.
	 * <strong>default: false</strong>, unless {@code fluent=true}, then <strong>default: true</strong>
	 * 
	 * @return Whether or not setters should return themselves (chaining) or {@code void} (no chaining).
	 */
	boolean chain() default false;
	
	/**
	 * If present, only fields with any of the stated prefixes are given the getter/setter treatment.
	 * Note that a prefix only counts if the next character is NOT a lowercase character or the last
	 * letter of the prefix is not a letter (for instance an underscore). If multiple fields
	 * all turn into the same name when the prefix is stripped, an error will be generated.
	 * 
	 * @return If you are in the habit of prefixing your fields (for example, you name them {@code fFieldName}, specify such prefixes here).
	 */
	String[] prefix() default {};
}

@Data
//@AllArgsConstructor
//@NoArgsConstructor
@TableName("test_user1")
@Accessors(chain = false,fluent = false)
public class User1 {
    @TableId(value = "id", type = IdType.AUTO)
    private int xxId;
    private String yyUserName;
    private int zzAge;
    // 其他字段...

    public static void main(String[] args) {
        User1 user1 = new User1();

        user1.setXxId(123);
        user1.setYyUserName("manong");
        user1.setZzAge(123);

        System.out.println(user1); // User1(xxId=123, yyUserName=manong, zzAge=123)
        System.out.println(user1.getZzAge()); // 123

    }
}

@Data
@TableName("test_user1")
@Accessors(fluent = true)
public class User1 {
    @TableId(value = "id", type = IdType.AUTO)
    private int id;
    private String username;
    private int age;
    // 其他字段...

    public static void main(String[] args) {
        User1 user1 = new User1();

        System.out.println(user1.id()); // 这个返回的值是int值，因为id为int类型
        System.out.println(user1.id(123)); // 这个返回的对象值是类

        System.out.println(user1.id()); // 再次看看id的属性为，123
        System.out.println(user1.age()); // 查看其age属性，发现为0



    }
}

@Data
@TableName("test_user1")
@Accessors(chain = true)
public class User1 {
    @TableId(value = "id", type = IdType.AUTO)
    private int id;
    private String username;
    private int age;
    // 其他字段...

    public static void main(String[] args) {
        User1 user1 = new User1();

//        System.out.println(user1.setId(123)); // 返回对象
        user1.setAge(123).setUsername("manong");
        System.out.println(user1); // User1(id=0, username=manong, age=123)
        System.out.println(user1.getAge()); // 123


        User1 user2 = new User1().setAge(333).setUsername("yanjiuseng");
        System.out.println(user2); // User1(id=0, username=yanjiuseng, age=333)


    }
}

@Data
@TableName("test_user1")
@Accessors(prefix = {"xx","yy","zz"})
public class User1 {
    @TableId(value = "id", type = IdType.AUTO)
    private int xxId;
    private String yyUserName;
    private int zzAge;
    // 其他字段...

    public static void main(String[] args) {
        User1 user1 = new User1();

        user1.setId(123);
        user1.setUserName("manong");
        user1.setAge(123);

        System.out.println(user1); // User1(xxId=123, yyUserName=manong, zzAge=123)
        System.out.println(user1.getAge()); // 123

    }
}