这篇文章主要介绍了如何使用maven构建java9 service，具有一定借鉴价值，感兴趣的朋友可以参考下，希望大家阅读完这篇文章之后大有收获，下面让小编带着大家一起了解一下。
maven
整个工程跟传统maven多module的工程结构一样，java9的一个module对应maven project的一个module。下面是根目录下的pom文件：
<?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>com.example</groupId> <artifactId>java9-service-demo</artifactId> <version>0.0.1-SNAPSHOT</version> <modules> <module>consumer-demo</module> <module>service-sort</module> <module>service-sort-bubble</module> <module>service-sort-merge</module> </modules> <packaging>pom</packaging> <properties> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <!--让intellij能够正确编译java9，不然老是变回使用1.5--> <maven.compiler.source>9</maven.compiler.source> <maven.compiler.target>9</maven.compiler.target> </properties> <build> <pluginManagement> <plugins> <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-compiler-plugin</artifactId> <version>3.6.1</version> <configuration> <release>9</release> </configuration> </plugin> </plugins> </pluginManagement> </build> </project>
这里管理了一个maven-compiler-plugin，配置release为9，因为java9支持multi release，可以同时支持多个java版本，这里编译为java9版本。
service-sort
这个是service接口module
module service.sort {
exports service.sort;
uses service.sort.SortService;
}这里同时声明uses SortService表示是它需要在这个module里头使用ServiceLoader去加载service实例
public interface SortService {
public <T extends Comparable> List<T> sortList(List<T> list);
public static SortService getProviderInstanceLazy() {
Stream<Provider<SortService>> providers = ServiceLoader.load(SortService.class)
.stream();
//provider方法等到get的时候才会实例化
SortService service = providers.map(Provider::get)
.findAny()
.orElse(null);
return service;
}
}这里在声明接口的同时，也增加了静态方法，用于加载service实例。
service-sort-bubble
maven
<?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"> <parent> <artifactId>java9-service-demo</artifactId> <groupId>com.example</groupId> <version>0.0.1-SNAPSHOT</version> </parent> <modelVersion>4.0.0</modelVersion> <groupId>com.example</groupId> <artifactId>service-sort-bubble</artifactId> <packaging>jar</packaging> <dependencies> <dependency> <groupId>com.example</groupId> <artifactId>service-sort</artifactId> <version>0.0.1-SNAPSHOT</version> </dependency> </dependencies> </project>
这里添加对api包的依赖
module-info.java
module service.sort.bubble {
requires service.sort;
provides service.sort.SortService with sort.impl.bubble.BubbleSort;
}这里声明了BubbleSort提供了SortService的实现
BubbleSort
public class BubbleSort implements SortService {
public <T extends Comparable> List<T> sortList(List<T> list) {
System.out.println("use BubbleSort");
for (int outer = 0; outer < list.size() - 1; outer++) {
for (int inner = 0; inner < list.size()-outer-1; inner++) {
if (list.get(inner).compareTo(list.get(inner + 1)) > 0) {
swap(list, inner);
}
}
}
return list;
}
private <T> void swap(List<T>list, int inner) {
T temp = list.get(inner);
list.set(inner, list.get(inner + 1));
list.set(inner + 1, temp);
}
}service-sort-merge
maven
<?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"> <parent> <artifactId>java9-service-demo</artifactId> <groupId>com.example</groupId> <version>0.0.1-SNAPSHOT</version> </parent> <modelVersion>4.0.0</modelVersion> <groupId>com.example</groupId> <artifactId>service-sort-merge</artifactId> <packaging>jar</packaging> <dependencies> <dependency> <groupId>com.example</groupId> <artifactId>service-sort</artifactId> <version>0.0.1-SNAPSHOT</version> </dependency> </dependencies> </project>
module-info.java
module service.sort.merge {
requires service.sort;
provides service.sort.SortService with sort.impl.merge.MergeSort;
}这里声明了MergeSort为SortService接口的实现
MergeSort
import java.util.List;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Arrays;
import service.sort.SortService;
public class MergeSort implements SortService {
public <T extends Comparable> List<T> sortList(List<T> list) {
System.out.println("using MergeSort");
Collections.sort(list);
return list;
}
}consumer
maven
<?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"> <parent> <artifactId>java9-service-demo</artifactId> <groupId>com.example</groupId> <version>0.0.1-SNAPSHOT</version> </parent> <modelVersion>4.0.0</modelVersion> <groupId>com.example</groupId> <artifactId>consumer-demo</artifactId> <packaging>jar</packaging> <dependencies> <dependency> <groupId>com.example</groupId> <artifactId>service-sort</artifactId> <version>0.0.1-SNAPSHOT</version> </dependency> </dependencies> </project>
注意这里没有添加实现类的依赖
module-info.java
module consumer {
requires service.sort;
}Main
public class Main {
public static void main(String[] args) {
System.out.println("sort service consumer started.");
List<Integer> data = new ArrayList<Integer>();
data.add(5);
data.add(3);
data.add(10);
data.add(2);
data.add(8);
SortService sortService = SortService.getProviderInstanceLazy();
if (sortService != null) {
sortService.sortList(data);
}
System.out.println(data);
System.out.println("finish");
}
}编译及运行
编译
mvn clean install
这里是在根目录下执行
使用bubble
复制代码 代码如下:
java --module-path ./consumer-demo/target/consumer-demo-0.0.1-SNAPSHOT.jar:./service-sort/target/service-sort-0.0.1-SNAPSHOT.jar:./service-sort-bubble/target/service-sort-bubble-0.0.1-SNAPSHOT.jar --module consumer/consumer.Main
注意这里添加了bubble的jar到module-path
输出
sort service consumer started.
use BubbleSort
[2, 3, 5, 8, 10]
finish
使用merge
复制代码 代码如下:
java --module-path ./consumer-demo/target/consumer-demo-0.0.1-SNAPSHOT.jar:./service-sort/target/service-sort-0.0.1-SNAPSHOT.jar:./service-sort-merge/target/service-sort-merge-0.0.1-SNAPSHOT.jar --module consumer/consumer.Main
注意这里添加了merge的jar到module-path
输出
sort service consumer started.
using MergeSort
[2, 3, 5, 8, 10]
finish
两个service实现都添加
复制代码 代码如下:
java --module-path ./consumer-demo/target/consumer-demo-0.0.1-SNAPSHOT.jar:./service-sort/target/service-sort-0.0.1-SNAPSHOT.jar:./service-sort-bubble/target/service-sort-bubble-0.0.1-SNAPSHOT.jar:./service-sort-merge/target/service-sort-merge-0.0.1-SNAPSHOT.jar --module consumer/consumer.Main
或者
复制代码 代码如下:
java --module-path ./consumer-demo/target/consumer-demo-0.0.1-SNAPSHOT.jar:./service-sort/target/service-sort-0.0.1-SNAPSHOT.jar:./service-sort-merge/target/service-sort-merge-0.0.1-SNAPSHOT.jar:./service-sort-bubble/target/service-sort-bubble-0.0.1-SNAPSHOT.jar --module consumer/consumer.Main
输出
sort service consumer started.
use BubbleSort
[2, 3, 5, 8, 10]
finish
发现貌似跟添加到path的顺序没有关系，即使把merge的jar包放在前面，也是使用bubble
感谢你能够认真阅读完这篇文章，希望小编分享的“如何使用maven构建java9 service”这篇文章对大家有帮助，同时也希望大家多多支持亿速云，关注亿速云行业资讯频道，更多相关知识等着你来学习!
免责声明：本站发布的内容（图片、视频和文字）以原创、转载和分享为主，文章观点不代表本网站立场，如果涉及侵权请联系站长邮箱：is@yisu.com进行举报，并提供相关证据，一经查实，将立刻删除涉嫌侵权内容。
