spring MVC使用及新特性說明

1、      spring MVC使用簡述

配置部分：

jar包和依賴jar包

​ <?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/maven-v4_0_0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>org.springframework.samples</groupId> <artifactId>test</artifactId> <name>test</name> <packaging>war</packaging> <version>1.0.0-BUILD-SNAPSHOT</version> <properties> <java-version>1.7</java-version> <org.springframework-version>4.2.2.RELEASE</org.springframework-version> <org.springframework.security-version>4.0.1.RELEASE</org.springframework.security-version> <org.mybatis-version>3.3.0</org.mybatis-version> <org.aspectj-version>1.8.1</org.aspectj-version> <org.slf4j-version>1.7.12</org.slf4j-version> </properties> <dependencies> <!-- Spring --> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-context</artifactId> <version>${org.springframework-version}</version> <exclusions> <!-- Exclude Commons Logging in favor of SLF4j --> <exclusion> <groupId>commons-logging</groupId> <artifactId>commons-logging</artifactId> </exclusion> </exclusions> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-webmvc</artifactId> <version>${org.springframework-version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-tx</artifactId> <version>${org.springframework-version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-jdbc</artifactId> <version>${org.springframework-version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-aspects</artifactId> <version>${org.springframework-version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-test</artifactId> <version>${org.springframework-version}</version> </dependency> <dependency> <groupId>org.springframework.session</groupId> <artifactId>spring-session</artifactId> <version>1.1.1.RELEASE</version> </dependency> <!-- AspectJ --> <dependency> <groupId>org.aspectj</groupId> <artifactId>aspectjrt</artifactId> <version>${org.aspectj-version}</version> </dependency> <!-- mybatis --> <dependency> <groupId>org.mybatis</groupId> <artifactId>mybatis</artifactId> <version>${org.mybatis-version}</version> </dependency> <!-- mybatis-spring --> <dependency> <groupId>org.mybatis</groupId> <artifactId>mybatis-spring</artifactId> <version>1.2.3</version> </dependency> <!-- mybatis-mysql --> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>5.1.38</version> </dependency> <!-- druid --> <dependency> <groupId>com.alibaba</groupId> <artifactId>druid</artifactId> <version>1.0.17</version> </dependency> <dependency> <groupId>net.sourceforge.jtds</groupId> <artifactId>jtds</artifactId> <version>1.2.4</version> </dependency> <!-- kryo --> <dependency> <groupId>com.esotericsoftware</groupId> <artifactId>kryo</artifactId> <version>3.0.3</version> </dependency> <dependency> <groupId>com.esotericsoftware</groupId> <artifactId>kryo-shaded</artifactId> <version>3.0.3</version> </dependency> <!-- Logging --> <dependency> <groupId>org.slf4j</groupId> <artifactId>slf4j-api</artifactId> <version>${org.slf4j-version}</version> </dependency> <dependency> <groupId>org.slf4j</groupId> <artifactId>jcl-over-slf4j</artifactId> <version>${org.slf4j-version}</version> <scope>runtime</scope> </dependency> <dependency> <groupId>org.slf4j</groupId> <artifactId>slf4j-log4j12</artifactId> <version>${org.slf4j-version}</version> <scope>runtime</scope> </dependency> <dependency> <groupId>log4j</groupId> <artifactId>log4j</artifactId> <version>1.2.16</version> <scope>runtime</scope> </dependency> <!-- @Inject --> <dependency> <groupId>javax.inject</groupId> <artifactId>javax.inject</artifactId> <version>1</version> </dependency> <!-- Servlet --> <dependency> <groupId>org.apache.tomcat</groupId> <artifactId>tomcat-servlet-api</artifactId> <version>7.0.30</version> <scope>provided</scope> </dependency> <dependency> <groupId>javax.servlet.jsp</groupId> <artifactId>jsp-api</artifactId> <version>2.1</version> <scope>provided</scope> </dependency> <dependency> <groupId>javax.servlet.jsp.jstl</groupId> <artifactId>jstl-api</artifactId> <version>1.2</version> <exclusions> <exclusion> <groupId>javax.servlet</groupId> <artifactId>servlet-api</artifactId> </exclusion> </exclusions> </dependency> <dependency> <groupId>org.glassfish.web</groupId> <artifactId>jstl-impl</artifactId> <version>1.2</version> <exclusions> <exclusion> <groupId>javax.servlet</groupId> <artifactId>servlet-api</artifactId> </exclusion> </exclusions> </dependency> <!-- commons-lang --> <dependency> <groupId>commons-lang</groupId> <artifactId>commons-lang</artifactId> <version>2.6</version> </dependency> <!-- commons-codec --> <dependency> <groupId>commons-codec</groupId> <artifactId>commons-codec</artifactId> <version>1.10</version> </dependency> <!-- redis --> <dependency> <groupId>org.springframework.data</groupId> <artifactId>spring-data-redis</artifactId> <version>1.6.4.RELEASE</version> </dependency> <dependency> <groupId>redis.clients</groupId> <artifactId>jedis</artifactId> <version>2.8.1</version> </dependency> <!-- Gson --> <dependency> <groupId>com.google.code.gson</groupId> <artifactId>gson</artifactId> <version>2.7</version> </dependency> <!-- Jackson JSON Processor --> <dependency> <groupId>com.fasterxml.jackson.core</groupId> <artifactId>jackson-databind</artifactId> <version>2.5.3</version> </dependency> <!-- Rome Atom+RSS --> <dependency> <groupId>com.rometools</groupId> <artifactId>rome</artifactId> <version>1.5.0</version> </dependency> <!-- JSR 303 with Hibernate Validator --> <dependency> <groupId>javax.validation</groupId> <artifactId>validation-api</artifactId> <version>1.0.0.GA</version> </dependency> <dependency> <groupId>org.hibernate</groupId> <artifactId>hibernate-validator</artifactId> <version>4.1.0.Final</version> </dependency> <!-- Joda Time Library --> <dependency> <groupId>joda-time</groupId> <artifactId>joda-time</artifactId> <version>2.3</version> </dependency> <!-- File Upload --> <dependency> <groupId>commons-fileupload</groupId> <artifactId>commons-fileupload</artifactId> <version>1.2.2</version> </dependency> <dependency> <groupId>commons-io</groupId> <artifactId>commons-io</artifactId> <version>2.0.1</version> </dependency> <!-- commons-dbcp --> <dependency> <groupId>commons-lang</groupId> <artifactId>commons-lang</artifactId> <version>2.2</version> </dependency> <dependency> <groupId>commons-dbcp</groupId> <artifactId>commons-dbcp</artifactId> <version>1.4</version> </dependency> <!-- Security (used for CSRF protection only) --> <dependency> <groupId>org.springframework.security</groupId> <artifactId>spring-security-web</artifactId> <version>${org.springframework.security-version}</version> </dependency> <!-- Test --> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-test</artifactId> <version>${org.springframework-version}</version> <scope>test</scope> </dependency> <dependency> <groupId>junit</groupId> <artifactId>junit</artifactId> <version>4.11</version> <scope>test</scope> </dependency> <dependency> <groupId>xmlunit</groupId> <artifactId>xmlunit</artifactId> <version>1.2</version> <scope>test</scope> </dependency> <dependency> <groupId>com.jayway.jsonpath</groupId> <artifactId>json-path</artifactId> <version>0.8.1</version> </dependency> <dependency> <groupId>org.hamcrest</groupId> <artifactId>hamcrest-library</artifactId> <version>1.3</version> <scope>test</scope> </dependency> <!-- XStream --> <dependency> <groupId>com.thoughtworks.xstream</groupId> <artifactId>xstream</artifactId> <version>1.4.4</version> </dependency> </dependencies> <repositories> <!-- For testing against latest Spring snapshots --> <repository> <id>org.springframework.maven.snapshot</id> <name>Spring Maven Snapshot Repository</name> <url>http://repo.spring.io/snapshot</url> <releases> <enabled>false</enabled> </releases> <snapshots> <enabled>true</enabled> </snapshots> </repository> <!-- For developing against latest Spring milestones --> <repository> <id>org.springframework.maven.milestone</id> <name>Spring Maven Milestone Repository</name> <url>http://repo.spring.io/milestone</url> <snapshots> <enabled>false</enabled> </snapshots> </repository> </repositories> <build> <finalName>${project.artifactId}</finalName> <plugins> <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-compiler-plugin</artifactId> <version>2.3.2</version> <configuration> <encoding>UTF-8</encoding> <source>${java-version}</source> <target>${java-version}</target> </configuration> </plugin> <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-surefire-plugin</artifactId> <version>2.12</version> <configuration> <encoding>UTF-8</encoding> <includes> <include>**/*Tests.java</include> </includes> <excludes> <exclude>**/Abstract*.java</exclude> </excludes> <junitArtifactName>junit:junit</junitArtifactName> <argLine>-Xmx512m</argLine> </configuration> </plugin> <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-dependency-plugin</artifactId> <executions> <execution> <id>install</id> <phase>install</phase> <goals> <goal>sources</goal> </goals> </execution> </executions> </plugin> <plugin> <groupId>org.codehaus.mojo</groupId> <artifactId>aspectj-maven-plugin</artifactId> <!-- Have to use version 1.2 since version 1.3 does not appear to work with ITDs --> <version>1.2</version> <dependencies> <dependency> <groupId>org.aspectj</groupId> <artifactId>aspectjrt</artifactId> <version>${org.aspectj-version}</version> </dependency> <dependency> <groupId>org.aspectj</groupId> <artifactId>aspectjtools</artifactId> <version>${org.aspectj-version}</version> </dependency> </dependencies> <executions> <execution> <goals> <goal>compile</goal> <goal>test-compile</goal> </goals> </execution> </executions> <configuration> <outxml>true</outxml> <source>${java-version}</source> <target>${java-version}</target> </configuration> </plugin> <plugin> <groupId>org.apache.tomcat.maven</groupId> <artifactId>tomcat7-maven-plugin</artifactId> <version>2.2</version> </plugin> <plugin> <groupId>org.eclipse.jetty</groupId> <artifactId>jetty-maven-plugin</artifactId> <version>9.0.6.v20130930</version> <configuration> <webApp> <contextPath>/${project.artifactId}</contextPath> </webApp> </configuration> </plugin> </plugins> </build> </project> ​

前端控制器配置(web.xml):

<servlet>

    <servlet-name>appServlet</servlet-name>

    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>

    <load-on-startup>1</load-on-startup>

</servlet>

<servlet-mapping>

    <servlet-name>appServlet</servlet-name>

    <url-pattern>/</url-pattern>

</servlet-mapping>

load-on-startup：表示啓動容器時初始化該Servlet；

url-pattern：表示哪些請求交給Spring Web MVC處理， 「/」 是用來定義默認servlet映射的。「*.html」表示攔截全部以html爲擴展名的請求。

 

spring配置文件(appServlet-servlet.xml):

<beans:bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">

        <beans:property name="prefix" value="/WEB-INF/views/" />

        <beans:property name="suffix" value=".jsp" />

</beans:bean>

<context:component-scan base-package=" com.huntkey.ruixin.demo.web" />

<bean class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter"/>

InternalResourceViewResolver：用於支持Servlet、JSP視圖解析；

prefix和suffix：查找視圖頁面的前綴和後綴（前綴[邏輯視圖名]後綴），好比傳進來的邏輯視圖名爲hello，則該該jsp視圖頁面應該存放在「WEB-INF/jsp/hello.jsp」；

context:component-scan:配合@Controller註解使用，讓spring找到定義爲Controller的bean。 對web包中的全部類進行掃描，以完成Bean建立和自動依賴注入的功能 ;

AnnotationMethodHandlerAdapter: 啓動Spring MVC的註解功能，完成請求和註解POJO的映射

 

 

編碼部分：

Controller：

@Controller註解將class定義爲一個controller類。

@ RequestMapping 處理請求地址映射，可註解類或者方法前。註解的六個參數：

@RequestMapping註解參數

參數	描述
value	請求的實際地址
method	請求的method類型(GET/POST/PUT/DELETE)
consumes	指處理請求的提交內容類型(Content-Type)，如application/json, text/html
produces	返回的內容類型，僅當request請求頭中的(Accept)中包含該指定類型才返回
params	指定request中必須包含某些參數值，才讓該方法處理
headers	指定request中必須包含某些指定的header值，才能讓該方法處理請求

eg.

@RequestMapping(value="/owners/{ownerId}", method=RequestMethod.GET)

@RequestMapping("/spring-web/{symbolicName:[a-z-]+}-{version:\d\.\d\.\d}.{extension:\.[a-z]}")

@RequestMapping(value = "/pets", consumes="application/json")

@RequestParam：通常用於將指定的請求參數匹配方法中的形參。

 

public String test(@RequestParam("a")String b) {}就會將a參數的值賦給b.

@RequestMapping(value="html", method=RequestMethod.GET)
public String prepare(Model model) {
    model.addAttribute("foo", "bar");
    model.addAttribute("fruit", "apple");
    return "views/html";
}

SpringMVC會自動將請求參數封裝進model中，能夠把model理解爲一個Map

 

數據校驗：

在JavaBean定義時能夠添加經常使用的數據驗證類註解。

javax.validation.constraints和org.hibernate.validator.constraints中提供經常使用的數據校驗註解

 

Bean Validation 中內置的 constraint

Constraint	詳細信息
@Null	被註釋的元素必須爲 null
@NotNull	被註釋的元素必須不爲 null
@AssertTrue	被註釋的元素必須爲 true
@AssertFalse	被註釋的元素必須爲 false
@Min(value)	被註釋的元素必須是一個數字，其值必須大於等於指定的最小值
@Max(value)	被註釋的元素必須是一個數字，其值必須小於等於指定的最大值
@DecimalMin(value)	被註釋的元素必須是一個數字，其值必須大於等於指定的最小值
@DecimalMax(value)	被註釋的元素必須是一個數字，其值必須小於等於指定的最大值
@Size(max, min)	被註釋的元素的大小必須在指定的範圍內
@Digits (integer, fraction)	被註釋的元素必須是一個數字，其值必須在可接受的範圍內
@Past	被註釋的元素必須是一個過去的日期
@Future	被註釋的元素必須是一個未來的日期
@Pattern(value)	被註釋的元素必須符合指定的正則表達式

 

 

Hibernate Validator 附加的 constraint

Constraint	詳細信息
@Email	被註釋的元素必須是電子郵箱地址
@Length	被註釋的字符串的大小必須在指定的範圍內
@NotEmpty	被註釋的字符串的必須非空
@Range	被註釋的元素必須在合適的範圍內

 

org.springframework.format.annotation中提供數字和日期格式驗證註解

此外，經過實現javax.validation.ConstraintValidator接口能夠自定義驗證註解。

eg.

public class JavaBean {

    @NotNull

    @Max(5)

    private Integer number;

    @NotNull

    @Future

    @DateTimeFormat(iso=ISO.DATE)

    private Date date;

}

在Controller中用@Valid配合BindingResult使用能夠將JavaBean的校驗結果自動放入result中

 

BindingResult 對象必須在 @Valid 的緊挨着的後面，不然接收不到錯誤信息。
 

public @ResponseBody String validate(@RequestBody @Valid JavaBean bean, BindingResult result) {

        if (result.hasErrors()) {

            return "Object has validation errors";

        } else {

            return "No errors";

        }

    }

 

異常處理：

springMVC提供兩種異常處理方法

第一種 局部異常處理

在controller中經過註解@ExceptionHandler配置，這對當前controller中每一個有@requestMapping註解的方法都有效。

@Controller

public class ExceptionController {

    @RequestMapping("/exception")

    public @ResponseBody String exception() {

        throw new IllegalStateException("Sorry!");

    }

    @ExceptionHandler

    public @ResponseBody String handle(IllegalStateException e,HttpServletRequest req) {

        return "IllegalStateException handled!";

    }

 }

第二種 全局異常處理

用@ControllerAdvice註解的異常處理器，針對所有controller

@ControllerAdvice

public class GlobalExceptionHandler {

    @ExceptionHandler

    public @ResponseBody String handleBusinessException(BusinessException ex) {

        return "Handled BusinessException";

    }

}

文件上傳：

appServlet-servlet.xml中配置multipar解析器

<beans:bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver" />

jsp中form設置屬性以支持上傳二進制數據：enctype="multipart/form-data"

<form id="fileuploadForm" action=""method="POST" enctype="multipart/form-data" class="cleanform"> </form>

controller中

public void processUpload(@RequestParam MultipartFile file, Model model) throws IOException {
    File f = new File("D:/fileupload/"+file.getOriginalFilename());
    file.transferTo(f);
    model.addAttribute("message", "File '" + file.getOriginalFilename() + "' uploaded successfully");
}