The scalawebapp from derfighyt

看了一些scala的语法，写了点简单的脚本后，打算尝试用scala开发web应用。因为目前主要在用spring做java的web开发，如果放弃现有的技术框架成本太高，所以目标是能够继承spring和scala，既能依靠之前的技术栈，又可以尝试scala的特性。尝试开始：

#搭建项目框架在网上找了一些scala web相关的说明，但是没有符合需求的，有提到用SBT或者scala的一些框架，也有说spring-scala和spring-boot。 spring-scala的最新版本是2013年发布的，不知道是不是还在更新，SBT的例子基本是直接继承Servlet，没有利用到spring，而我最终的目的是能够继续使用Maven，Jenkins这一套，所以决定还是回归老本行，先搭一个简单的java web项目。

##创建Java Web项目正常创建Java Web项目，导入Maven支持，调整目录结构和pom文件，顺手建了src/main/scala目录备用。

加入web.xml，log4j.xml，spring-web-servlet.xml三个配置文件

###pom.xml 需要引入scala-maven-plugin和scala相关的依赖，scalatra依赖的akka-actor报错，单独引用

<?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.derfy</groupId>
    <artifactId>scala-web-app</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>war</packaging>

    <name>scalaWebApp</name>
    <description>learning to build a web application based on scala</description>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
        <scala.version>2.11.8</scala.version>
    </properties>

    <repositories>
        <repository>
            <id>scalaz</id>
            <name>scalaz</name>
            <url>http://dl.bintray.com/scalaz/releases</url>
        </repository>
        <repository>
            <id>central</id>
            <name>Maven Repository Switchboard</name>
            <url>http://repo1.maven.org/maven2</url>
        </repository>
        <repository>
            <id>milestone.repo.springsource.org</id>
            <name>repo.springsource.org-milestone</name>
            <url>https://repo.springsource.org/libs-milestone</url>
        </repository>
    </repositories>

    <build>
        <resources>
            <resource>
                <directory>src/main/java</directory>
                <includes>
                    <include>**/*.xml</include>
                </includes>
            </resource>
            <resource>
                <directory>src/main/resources/</directory>
                <includes>
                    <include>*.properties</include>
                    <include>*.xml</include>
                </includes>
            </resource>
            <resource>
                <directory>src/main/resources/spring</directory>
                <targetPath>spring</targetPath>
                <includes>
                    <include>*.xml</include>
                </includes>
            </resource>
        </resources>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.1</version>
                <configuration>
                    <source>1.8</source> <!-- 源代码使用的开发版本 -->
                    <target>1.8</target> <!-- 需要生成的目标class文件的编译版本 -->
                </configuration>
            </plugin>
            <plugin>
                <groupId>net.alchim31.maven</groupId>
                <artifactId>scala-maven-plugin</artifactId>
                <version>3.2.1</version>
                <executions>
                    <execution>
                        <goals>
                            <goal>compile</goal>
                            <goal>testCompile</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
            <plugin>
                <groupId>org.codehaus.mojo</groupId>
                <artifactId>build-helper-maven-plugin</artifactId>
                <executions>
                    <execution>
                        <id>add-source</id>
                        <phase>generate-sources</phase>
                        <goals>
                            <goal>add-source</goal>
                        </goals>
                        <configuration>
                            <sources>
                                <source>src/main/scala</source>
                            </sources>
                        </configuration>
                    </execution>
                    <execution>
                        <id>add-test-source</id>
                        <phase>generate-sources</phase>
                        <goals>
                            <goal>add-test-source</goal>
                        </goals>
                        <configuration>
                            <sources>
                                <source>src/test/scala</source>
                            </sources>
                        </configuration>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>

    <dependencies>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>4.2.5.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.scala-lang</groupId>
            <artifactId>scala-library</artifactId>
            <version>${scala.version}</version>
            <scope>compile</scope>
        </dependency>
        <dependency>
            <groupId>org.scala-lang</groupId>
            <artifactId>scala-compiler</artifactId>
            <version>${scala.version}</version>
            <scope>compile</scope>
        </dependency>
        <dependency>
            <groupId>org.scala-lang</groupId>
            <artifactId>scala-reflect</artifactId>
            <version>${scala.version}</version>
        </dependency>
        <dependency>
            <groupId>org.scala-lang</groupId>
            <artifactId>scala-actors</artifactId>
            <version>${scala.version}</version>
        </dependency>
        <dependency>
            <groupId>com.typesafe.akka</groupId>
            <artifactId>akka-actor_2.10</artifactId>
            <version>2.2-M3</version>
        </dependency>
        <dependency>
            <groupId>org.scalatra</groupId>
            <artifactId>scalatra</artifactId>
            <version>2.2.0</version>
            <exclusions>
                <exclusion>
                    <groupId>com.typesafe.akka</groupId>
                    <artifactId>akka-actor</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>servlet-api</artifactId>
            <version>2.5</version>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>log4j</groupId>
            <artifactId>log4j</artifactId>
            <version>1.2.16</version>
        </dependency>
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-log4j12</artifactId>
            <version>1.7.5</version>
        </dependency>
    </dependencies>

</project>

###web.xml 正常web项目的配置，指定过滤器，log4j，使用spring的DispatcherServlet

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
		  http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
         version="2.5">

    <filter>
        <filter-name>characterEncodingFilter</filter-name>
        <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
        <init-param>
            <param-name>encoding</param-name>
            <param-value>UTF-8</param-value>
        </init-param>
        <init-param>
            <param-name>forceEncoding</param-name>
            <param-value>true</param-value>
        </init-param>
    </filter>

    <filter-mapping>
        <filter-name>characterEncodingFilter</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>

    <!-- log 配置-->
    <context-param>
        <param-name>log4jConfigLocation</param-name>
        <param-value>classpath:log4j.xml</param-value>
    </context-param>
    <context-param>
        <param-name>log4jRefreshInterval</param-name>
        <param-value>60000</param-value>
    </context-param>
    <listener>
        <listener-class>org.springframework.web.util.Log4jConfigListener</listener-class>
    </listener>

    <context-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>classpath:/spring/spring-web-servlet.xml</param-value>
    </context-param>
    <listener>
        <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
    </listener>

    <servlet>
        <servlet-name>scala</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <init-param>
            <param-name>contextAttribute</param-name>
            <param-value>org.springframework.web.context.WebApplicationContext.ROOT</param-value>
        </init-param>
        <load-on-startup>1</load-on-startup>
    </servlet>
    <servlet-mapping>
        <servlet-name>scala</servlet-name>
        <url-pattern>/*</url-pattern>
    </servlet-mapping>

    <context-param>
        <param-name>webAppRootKey</param-name>
        <param-value>scala.webapp.root</param-value>
    </context-param>

    <welcome-file-list>
        <welcome-file>index.jsp</welcome-file>
    </welcome-file-list>

    <display-name>scala.webapp</display-name>

</web-app>

###log4j.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE log4j:configuration SYSTEM "log4j.dtd">
<log4j:configuration xmlns:log4j="http://jakarta.apache.org/log4j/">

    <appender name="CONSOLE" class="org.apache.log4j.ConsoleAppender">
        <param name="encoding" value="UTF-8"/>
        <layout class="org.apache.log4j.PatternLayout">
            <param name="ConversionPattern" value="%d %-5p [%c{1}] %m%n" />
        </layout>
    </appender>

    <root>
        <priority value="INFO" />
        <appender-ref ref="CONSOLE" />
    </root>

</log4j:configuration>

###spring-web-servlet.xml 指定component-scan的位置，这里在实验时发现，我在src/main/java和src/main/scala下面定义了两个同名的包，运行时都能够被spring扫描到。

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:mvc="http://www.springframework.org/schema/mvc"
       xsi:schemaLocation="http://www.springframework.org/schema/context
        http://www.springframework.org/schema/context/spring-context-3.0.xsd
        http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
        http://www.springframework.org/schema/mvc
		http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd">

    <mvc:annotation-driven/>
    <mvc:default-servlet-handler/>

    <!-- 扫描 -->
    <context:annotation-config/>
    <context:component-scan base-package="com.derfy"/>
    
</beans>

##测试spring框架在src/main/java下面创建com.derfy.web.controller包，创建HelloJavaController.java ###HelloJavaController.java

package com.derfy.web.controller;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;

@Controller
@RequestMapping(path = "java")
public class HelloJavaController {

    @RequestMapping(path = "/hello")
    @ResponseBody
    public String hello() {
        return "hello java";
    }
}

配置tomcat，启动，浏览器输入http://localhost:8080/java/hello，输出"hello java"，项目成功启动。

##实验spring对scala的支持在src/main/scala下面创建com.derfy.web.controller包，创建HelloScalaController.scala 复制java代码过来自动转换为scala风格，做一些修改。注意这里直接按java的方式在类和方法上使用了spring的注解，但RequestMapping的path需要使用字符串数组。 ###HelloScalaController.scala

package com.derfy.web.controller

import org.springframework.stereotype.Controller
import org.springframework.web.bind.annotation.{RequestMapping, ResponseBody}

@Controller
@RequestMapping(path = Array("scala"))
class HelloScalaController {

  @RequestMapping(path = Array("/hello"))
  @ResponseBody
  def hello(): String = {
    "hello scala"
  }

}

启动tomcat，能够正常启动，输出如下日志，说明两个Controller类都被spring扫描到并加载。

2017-02-23 17:28:08,474 INFO  [RequestMappingHandlerMapping] Mapped "{[/java/hello]}" onto public java.lang.String com.derfy.web.controller.HelloJavaController.hello()
2017-02-23 17:28:08,476 INFO  [RequestMappingHandlerMapping] Mapped "{[/scala/hello]}" onto public java.lang.String com.derfy.web.controller.HelloScalaController.hello()

浏览器输入http://localhost:8080/scala/hello，输出"hello scala"，scala风格的Controller也可以成功运行。

尝试加入参数，PathVariable注解也可以正常使用 ###HelloScalaController.scala

package com.derfy.web.controller

import org.springframework.stereotype.Controller
import org.springframework.web.bind.annotation.{PathVariable, RequestMapping, ResponseBody}

@Controller
@RequestMapping(path = Array("scala"))
class HelloScalaController {

  @RequestMapping(path = Array("/hello"))
  @ResponseBody
  def hello(@PathVariable name: String): String = {
    "hello" + name
  }

}

derfighyt / scalawebapp Goto Github PK

scalawebapp's Introduction

scalawebapp's People

Watchers

Recommend Projects

React

Vue.js

Typescript

TensorFlow

Django

Laravel

D3

Recommend Topics

javascript

web

server

Machine learning

Visualization

Game

Recommend Org

Facebook

Microsoft

Google

Alibaba

D3

Tencent