lombok在IntelliJ IDEA下的使用
lombok是一款可以精减java代码、提升开发人员生产效率的辅助工具，利用注解在编译期自动生成setter/getter/toString()/constructor之类的代码。代码越少，意味着出bug的可能性越低。
官网地址：https://projectlombok.org/ 首页有一段几分钟的演示视频，看完就明白是怎么回事了。
先来二段对比代码：
这是用lombok后的java代码：
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import lombok.*;
import lombok.extern.slf4j.Slf4j;
import java.io.ByteArrayInputStream;
import java.io.*;
import java.util.ArrayList;
@Data
@Slf4j
@AllArgsConstructor
public class Something
{
private String
name;
private final String
country;
private final Object
lockObj = new Object();
public void sayHello(@NonNull String
target) {
String
content = String.format("hello,%s",
target);
System.out.println(content);
log.info(content);
}
public void addBalabala()
{
val
list = new ArrayList<String>();
list.add("haha");
System.out.println(list.size());
}
@SneakyThrows(IOException.class)
public void closeBalabala()
{
@Cleanup InputStream
is = new ByteArrayInputStream("hello
world".getBytes());
System.out.println(is.available());
}
@Synchronized("lockObj")
public void lockMethod()
{
System.out.println("test
lock method");
}
}
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等效于下面这段java代码：
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import java.beans.ConstructorProperties;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import lombok.NonNull;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
public class Something
{
private static final Logger
log = LoggerFactory.getLogger(Something.class);
private String
name;
private final String
country;
private final Object
lockObj = new Object();
public void sayHello(@NonNull String
target) {
if(target
== null)
{
throw new NullPointerException("target");
} else {
String
content = String.format("hello,%s", new Object[]{target});
System.out.println(content);
log.info(content);
}
}
public void addBalabala()
{
ArrayList
list = new ArrayList();
list.add("haha");
System.out.println(list.size());
}
public void closeBalabala()
{
try {
ByteArrayInputStream
$ex = new ByteArrayInputStream("hello
world".getBytes());
try {
System.out.println($ex.available());
} finally {
if(Collections.singletonList($ex).get(0)
!= null)
{
$ex.close();
}
}
} catch (IOException
var6) {
throw var6;
}
}
public void lockMethod()
{
Object
var1 = this.lockObj;
synchronized(this.lockObj)
{
System.out.println("test
lock method");
}
}
public String
getName() {
return this.name;
}
public String
getCountry() {
return this.country;
}
public Object
getLockObj() {
return this.lockObj;
}
public void setName(String
name) {
this.name
= name;
}
public boolean equals(Object
o) {
if(o
== this)
{
return true;
} else if(!(o instanceof Something))
{
return false;
} else {
Something
other = (Something)o;
if(!other.canEqual(this))
{
return false;
} else {
label47:
{
String this$name
= this.getName();
String
other$name = other.getName();
if(this$name
== null)
{
if(other$name
== null)
{
break label47;
}
} else if(this$name.equals(other$name))
{
break label47;
}
return false;
}
String this$country
= this.getCountry();
String
other$country = other.getCountry();
if(this$country
== null)
{
if(other$country
!= null)
{
return false;
}
} else if(!this$country.equals(other$country))
{
return false;
}
Object this$lockObj
= this.getLockObj();
Object
other$lockObj = other.getLockObj();
if(this$lockObj
== null)
{
if(other$lockObj
!= null)
{
return false;
}
} else if(!this$lockObj.equals(other$lockObj))
{
return false;
}
return true;
}
}
}
protected boolean canEqual(Object
other) {
return other instanceof Something;
}
public int hashCode()
{
boolean PRIME
= true;
byte result
= 1;
String
$name = this.getName();
int result1
= result * 59 +
($name == null?0:$name.hashCode());
String
$country = this.getCountry();
result1
= result1 * 59 +
($country == null?0:$country.hashCode());
Object
$lockObj = this.getLockObj();
result1
= result1 * 59 +
($lockObj == null?0:$lockObj.hashCode());
return result1;
}
public String
toString() {
return "Something(name=" + this.getName()
+ ",
country=" + this.getCountry()
+ ",
lockObj=" + this.getLockObj()
+ ")";
}
@ConstructorProperties({"name", "country"})
public Something(String
name, String country) {
this.name
= name;
this.country
= country;
}
}
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大概减少了2/3的代码，各种注解的详细用法，请参考：https://projectlombok.org/features/index.html
IDEA下使用时，可以通过插件的形式安装，插件下载地址：https://github.com/mplushnikov/lombok-intellij-plugin/releases
然后
Plugins -> Install plugin from disk... 选择下载的zip包安装，重启idea即可。
另外，还有一个关键设置：
为了让设置生效，建议再重启一次idea，然后就可以开心的编码了，可以ide里可以直接看到生成的方法：（下图中打红圈的都是自动生成的）