Lombok and Maven
POM
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<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>test</groupId>
<artifactId>test</artifactId>
<version>1.0-SNAPSHOT</version>
<properties>
<compiler.version>1.8</compiler.version>
<java_source_version>1.8</java_source_version>
<java_target_version>1.8</java_target_version>
<file_encoding>UTF-8</file_encoding>
</properties>
<dependencies>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<version>1.18.8</version>
<scope>provided</scope>
</dependency>
</dependencies>
<build>
<plugins>
<!-- Java Compiler -->
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<configuration>
<compilerVersion>${compiler.version}</compilerVersion>
<source>${java_source_version}</source>
<target>${java_target_version}</target>
<encoding>${file_encoding}</encoding>
</configuration>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-source-plugin</artifactId>
<executions>
<execution>
<id>attach-sources</id>
<goals>
<goal>jar</goal>
</goals>
</execution>
</executions>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-javadoc-plugin</artifactId>
<configuration>
<charset>${file_encoding}</charset>
<encoding>${file_encoding}</encoding>
</configuration>
<executions>
<execution>
<id>attach-javadocs</id>
<goals>
<goal>jar</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</project>
常用注解
-
@Data注解在类上；提供类所有属性的 getting 和 setting 方法，此外还提供了equals、canEqual、hashCode、toString 方法1 2 3 4 5 6 7
import lombok.Data; @Data public class Menu { private String shopId; private String skuMenuId; private String skuName; }
-
@Value: 注解在类上；注解和@Data类似，是@Data的不可变形式，区别在于它会把所有成员变量默认定义为final修饰，只提供getter方法，而不提供setter方法1 2 3 4 5 6 7 8 9 10 11
@Value public class LombokDemo { @NonNull private int id; //相当于 private final int id; public int getId() { return this.id; } }
-
@NonNull: 注解在property或者argument上，会自动产生一个关于此参数的非空检查，如果参数为空，则抛出一个空指针异常NullPointerException，也会有一个默认的无参构造方法。
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public void notNullExample(@NonNull String string) {
string.length();
}
//=>相当于
public void notNullExample(String string) {
if (string != null) {
string.length();
} else {
throw new NullPointerException("null");
}
}
@Cleanup：自动管理资源，用在局部变量之前，在当前变量范围内即将执行完毕退出之前会自动清理资源，自动生成try-finally这样的代码来关闭流
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public static void main(String[] args) {
try {
@Cleanup InputStream inputStream = new FileInputStream(args[0]);
} catch (FileNotFoundException e) {
e.printStackTrace();
}
//=>相当于
InputStream inputStream = null;
try {
inputStream = new FileInputStream(args[0]);
} catch (FileNotFoundException e) {
e.printStackTrace();
} finally {
if (inputStream != null) {
try {
inputStream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
-
@Builder： 被注解的类加个构造者模式 -
@Synchronized： 加个同步锁 -
@SneakyThrows: 这个注解用在 方法 上，可以将方法中的代码用try-catch语句包裹起来，捕获异常并在catch中用Lombok.sneakyThrow(e)把异常抛出，可以使用@SneakyThrows(Exception.class)的形式指定抛出哪种异常，也会生成默认的构造方法。
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import lombok.SneakyThrows;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.InputStream;
import java.io.UnsupportedEncodingException;
public class Test {
@SneakyThrows()
public void read() {
InputStream inputStream = new FileInputStream("");
}
@SneakyThrows
public void write() {
throw new UnsupportedEncodingException();
}
//相当于
public void read() throws FileNotFoundException {
InputStream inputStream = new FileInputStream("");
}
public void write() throws UnsupportedEncodingException {
throw new UnsupportedEncodingException();
}
}
参考：
