LOMBOK常用注解说明

lombok的安装说明，上一篇已经说过了这里就不再说明。

如果还可以的话可以打上一波
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常用的注解

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@Slf4j 由于自己开启日志需要写上

private  final Logger logger = LoggerFactory.getLogger(XXX.class);

为了方便，可以使用注解@Slf4j来直接使用log对象，简化了一行代码。。。
原来使用的就是logger.info("");这样的代码，现在就可以使用log.info("")
在使用中需要引入jar包import lombok.extern.slf4j.Slf4j;

@Setter
生成setter方法,final变量不包含

//原始类
@Setter
public class TestEntity {
 
    private String name;
 
    private Integer age;
 
    private final int type = 0;
}
//反编译的类
public class TestEntity {
    private String name;
    private Integer age;
    private final int type = 0;
 
    public TestEntity() {
    }
 
    public void setName(String name) {
        this.name = name;
    }
 
    public void setAge(Integer age) {
        this.age = age;
    }
}

@Getter
生成getter方法,final变量不包含

//原始类
@Getter
public class TestEntity {
 
    private String name;
 
    private Integer age;
 
    private final String type = "person";
}
//反编译的类
public class TestEntity {
    private String name;
    private Integer age;
    private final String type = "person";
 
    public TestEntity() {
    }
 
    public String getName() {
        return this.name;
    }
 
    public Integer getAge() {
        return this.age;
    }
 
    public String getType() {
        this.getClass();
        return "person";
    }
}

@NoArgsConstructor ： 生成无参构造
@AllArgsConstructor ： 生成全部参数构造
@RequiredArgsConstructor ： 通常与@NoNull注解连用，表示生成指定的有参构造

//原始类
@RequiredArgsConstructor
public class TestEntity {
 
    private String name;
    @NonNull
    private Integer age;
 
    private final String type = "person";
}
//反编译的类
public class TestEntity {
    private String name;
    @NonNull
    private Integer age;
    private final String type = "person";
 
    @ConstructorProperties({"age"})
    public TestEntity(@NonNull Integer age) {
        if(age == null) {
            throw new NullPointerException("age");
        } else {
            this.age = age;
        }
    }
}

@ToString ：生成所有属性的toString()方法
@EqualsAndHashCode：生成equals()方法和hashCode方法
@Data(常用)： @Data=@Setter+@Getter+@EqualsAndHashCode+@NoArgsConstructor

//原始类
@Data
public class TestEntity {
    @Setter(AccessLevel.PRIVATE)
    private String name;
 
    private Integer age;
 
    private final String type = "person";
}
//反编译的类
 
public class TestEntity {
    private String name;
    private Integer age;
    private final String type = "person";
 
    public TestEntity() {
    }
 
    public String getName() {
        return this.name;
    }
 
    public Integer getAge() {
        return this.age;
    }
 
    public String getType() {
        this.getClass();
        return "person";
    }
 
    public void setAge(Integer age) {
        this.age = age;
    }
 
    public boolean equals(Object o) {
     ...
    }
 
    protected boolean canEqual(Object other) {
        return other instanceof TestEntity;
    }
 
    public int hashCode() {
      ...
    }
 
    public String toString() {
        return "TestEntity(name=" + this.getName() + ", age=" + this.getAge() + ", type=" + this.getType() + ")";
    }
 
    private void setName(String name) {
        this.name = name;
    }
}

@Builder：构造Builder模式的结构。通过内部类Builder()进行构建对象。

//原始类
@Builder
public class TestEntity {
 
    private String name;
 
    private Integer age;
 
    private final String type = "person";
}
//反编译的类
public class TestEntity {
    private String name;
    private Integer age;
    private final String type = "person";
 
    @ConstructorProperties({"name", "age"})
    TestEntity(String name, Integer age) {
        this.name = name;
        this.age = age;
    }
 
    public static TestEntity.TestEntityBuilder builder() {
        return new TestEntity.TestEntityBuilder();
    }
 
    public static class TestEntityBuilder {
        private String name;
        private Integer age;
 
        TestEntityBuilder() {
        }
 
        public TestEntity.TestEntityBuilder name(String name) {
            this.name = name;
            return this;
        }
 
        public TestEntity.TestEntityBuilder age(Integer age) {
            this.age = age;
            return this;
        }
 
        public TestEntity build() {
            return new TestEntity(this.name, this.age);
        }
 
        public String toString() {
            return "TestEntity.TestEntityBuilder(name=" + this.name + ", age=" + this.age + ")";
        }
    }
}
 
//Builder模式使用方法
@Test
public  void test(){
    TestEntity testEntity = TestEntity.builder()
                    .name("java")
                    .age(18)
                    .build();
}
}

@Value：
与@Data相对应的@Value， 两个annotation的主要区别就是如果变量不加@NonFinal ，@Value会给所有的弄成final的。当然如果是final的话，就没有set方法了。

//原始类
@Value
public class TestEntity {
    @Setter(AccessLevel.PRIVATE)
    private String name;
 
    private Integer age;
 
    private final String type = "person";
}
//反编译的类
public final class TestEntity {
    private final String name;
    private final Integer age;
    private final String type = "person";
 
    @ConstructorProperties({"name", "age"})
    public TestEntity(String name, Integer age) {
        this.name = name;
        this.age = age;
    }
 
    public String getName() {
        return this.name;
    }
 
    public Integer getAge() {
        return this.age;
    }
 
    public String getType() {
        this.getClass();
        return "person";
    }
 
    public boolean equals(Object o) {
        if(o == this) {
            return true;
        } else if(!(o instanceof TestEntity)) {
            return false;
        } else {
            TestEntity other;
            label44: {
                other = (TestEntity)o;
                String this$name = this.getName();
                String other$name = other.getName();
                if(this$name == null) {
                    if(other$name == null) {
                        break label44;
                    }
                } else if(this$name.equals(other$name)) {
                    break label44;
                }
 
                return false;
            }
 
            Integer this$age = this.getAge();
            Integer other$age = other.getAge();
            if(this$age == null) {
                if(other$age != null) {
                    return false;
                }
            } else if(!this$age.equals(other$age)) {
                return false;
            }
 
            String this$type = this.getType();
            String other$type = other.getType();
            if(this$type == null) {
                if(other$type != null) {
                    return false;
                }
            } else if(!this$type.equals(other$type)) {
                return false;
            }
 
            return true;
        }
    }
 
    public int hashCode() {
        boolean PRIME = true;
        byte result = 1;
        String $name = this.getName();
        int result1 = result * 59 + ($name == null?43:$name.hashCode());
        Integer $age = this.getAge();
        result1 = result1 * 59 + ($age == null?43:$age.hashCode());
        String $type = this.getType();
        result1 = result1 * 59 + ($type == null?43:$type.hashCode());
        return result1;
    }
 
    public String toString() {
        return "TestEntity(name=" + this.getName() + ", age=" + this.getAge() + ", type=" + this.getType() + ")";
    }
}

@Synchronized： 同步方法

//原始类
public class TestEntity {
    private String name;
 
    private Integer age;
 
    private final String type = "person";
    @Synchronized
    public void write(){
        //do something
    }
}
//反编译的类
public class TestEntity {
    private final Object $lock = new Object[0];
    private String name;
    private Integer age;
    private final String type = "person";
 
    public TestEntity() {
    }
 
    public void write() {
        Object var1 = this.$lock;
        synchronized(this.$lock) {
            ;
        }
    }
}

@Cleanup @@SneakyThrows：自动调用close方法关闭资源。

//原始类
public class TestEntity {
    private String name;
 
    private Integer age;
 
    private final String type = "person";
 
    @SneakyThrows
    public  void  outputStream(){
         @Cleanup OutputStream outputStream = new FileOutputStream(new File("/Users/hello"));
    }
}
//反编译的类
public class TestEntity {
    private String name;
    private Integer age;
    private final String type = "person";
 
    public TestEntity() {
    }
 
    public void outputStream() {
        try {
            FileOutputStream $ex = new FileOutputStream(new File("/Users/hello"));
            if(Collections.singletonList($ex).get(0) != null) {
                $ex.close();
            }
 
        } catch (Throwable var2) {
            throw var2;
        }
    }
}

@async注解
启动加上@EnableAsync，需要执行异步方法加入@Async