在Java编程的过程中,我们在Code Entity的时候通常使用 IDE的generator来生成 get set toSting equals hashcode Constructor
等方法,有了lombok以后就不会了,它会在编译的过程中,分析AST抽象语法树的方式,把这些方法插入到编译以后的代码当中,这样做的好处可以降低代码量,让代码变得更容易读
程序源码
@Data
public class User {
int id;
String name;
}
编译后的代码
public class User {
int id;
String name;
public User() {
}
public int getId() {
return this.id;
}
public String getName() {
return this.name;
}
public void setId(int id) {
this.id = id;
}
public void setName(String name) {
this.name = name;
}
public boolean equals(Object o) {
if (o == this) {
return true;
} else if (!(o instanceof User)) {
return false;
} else {
User other = (User)o;
if (!other.canEqual(this)) {
return false;
} else if (this.getId() != other.getId()) {
return false;
} else {
Object this$name = this.getName();
Object other$name = other.getName();
if (this$name == null) {
if (other$name != null) {
return false;
}
} else if (!this$name.equals(other$name)) {
return false;
}
return true;
}
}
}
protected boolean canEqual(Object other) {
return other instanceof User;
}
public int hashCode() {
int PRIME = true;
int result = 1;
int result = result * 59 + this.getId();
Object $name = this.getName();
result = result * 59 + ($name == null ? 43 : $name.hashCode());
return result;
}
public String toString() {
return "User(id=" + this.getId() + ", name=" + this.getName() + ")";
}
}
使用方法
用法也非常简单 Maven 项目加上项目依赖就可以使用了,最新地址:https://projectlombok.org/setup/maven
<dependencies>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<version>1.16.18</version>
<scope>provided</scope>
</dependency>
</dependencies>
加载依赖之后IDE需要对应的plugin
Eclipse 下载 lombok.jar 运行java -jar lombok.jar
即可启动图形界面安装
https://projectlombok.org/setup/eclipse
Intellij就直接在plugins里面搜索资源安装重启即可
https://projectlombok.org/setup/intellij
其他更多IDE请浏览官方教程
https://projectlombok.org/setup/overview
Function and principle analysis 功能和原理分析
https://www.ibm.com/developerworks/cn/java/j-lombok/
http://notatube.blogspot.fr/2010/11/project-lombok-trick-explained.html
source code源码地址
https://github.com/rzwitserloot/lombok
Function intro功能介绍和使用教程
http://codepub.cn/2015/07/30/Lombok-development-guidelines/
http://i.woblog.cn/2016/06/19/use-lombok/
http://blog.csdn.net/ghsau/article/details/52334762
https://dzone.com/articles/lombok-reduces-your
project home page 项目主页
讨论组:
https://groups.google.com/forum/#!topic/project-lombok
Common Functions常用方法
@Data
@Data
All together now: A shortcut for
@ToString,
@EqualsAndHashCode,
@Getter on all fields, and
@Setter on all non-final fields, and
@RequiredArgsConstructor!
@Log
帮你注入Loger 支持多种 日志组件
@CommonsLog
Creates private static final org.apache.commons.logging.Log log = org.apache.commons.logging.LogFactory.getLog(LogExample.class);
@JBossLog
Creates private static final org.jboss.logging.Logger log = org.jboss.logging.Logger.getLogger(LogExample.class);
@Log
Creates private static final java.util.logging.Logger log = java.util.logging.Logger.getLogger(LogExample.class.getName());
@Log4j
Creates private static final org.apache.log4j.Logger log = org.apache.log4j.Logger.getLogger(LogExample.class);
@Log4j2
Creates private static final org.apache.logging.log4j.Logger log = org.apache.logging.log4j.LogManager.getLogger(LogExample.class);
@Slf4j
Creates private static final org.slf4j.Logger log = org.slf4j.LoggerFactory.getLogger(LogExample.class);
@XSlf4j
Creates private static final org.slf4j.ext.XLogger log = org.slf4j.ext.XLoggerFactory.getXLogger(LogExample.class);
Constructor
@NoArgsConstructor
@RequiredArgsConstructor
@AllArgsConstructor