Spring 4 MVC 视图解析器（XML JSON PDF等） 纯注解（带源码）【推荐】
原文地址：http://websystique.com/springmvc/spring-4-mvc-contentnegotiatingviewresolver-example/
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本文讲述Spring 4 MVC应用中通过Spring的 ContentNegotiatingViewResolver来支持多种形式的输出。
我们将输出 XML, JSON, PDF, XLS 和HTML格式的文件，基于纯注解的方式。
ContentNegotiatingViewResolver 是一个实现了 ViewResolver接口的类, 使用了请求媒体类型 (根据文件拓展吗 URL 指定输出类型参数或者accept 头)来选择合适的视图. ContentNegotiatingViewResolver 并不是自己进行处理而是代理到其他的ViewResolver 你可以配置处理的特定视图(XML,JSON,PDF,XLS,HTML,..).
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使用的技术或者软件
- Spring 4.0.6.RELEASE
- jackson-databind 2.4.1.3
- jackson-annotations 2.4.1
- lowagie itext 4.2.1
- Apache POI 3.10-beta2
- Maven 3
- JDK 1.6
- Tomcat 7.0.54
- Eclipse JUNO Service Release 2
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第 1步:创建文件夹结构
下面是最终的效果：
我们将使用纯注解的方式。
第2步: 修改pom.xml添加所需的依赖
<?xml version="1.0"?>
<project
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"
xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<modelVersion>4.0.0</modelVersion>
<groupId>com.websystique.springmvc</groupId>
<artifactId>Spring4MVCContentNegotiatingViewResolverExample</artifactId>
<packaging>war</packaging>
<version>1.0.0</version>
<name>Spring4MVCContentNegotiatingViewResolverExample</name>
<properties>
<springframework.version>4.0.6.RELEASE</springframework.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-core</artifactId>
<version>${springframework.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-web</artifactId>
<version>${springframework.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>${springframework.version}</version>
</dependency>
<!-- Needed for XML View (with JAXB2) -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-oxm</artifactId>
<version>${springframework.version}</version>
</dependency>
<!-- Needed for JSON View -->
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-databind</artifactId>
<version>2.4.1.3</version>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-annotations</artifactId>
<version>2.4.1</version>
</dependency>
<!-- Needed for PDF View -->
<dependency>
<groupId>com.lowagie</groupId>
<artifactId>itext</artifactId>
<version>4.2.1</version>
</dependency>
<!-- Needed for XLS View -->
<dependency>
<groupId>org.apache.poi</groupId>
<artifactId>poi</artifactId>
<version>3.10-beta2</version>
</dependency>
<!-- Servlet dependencies -->
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>javax.servlet-api</artifactId>
<version>3.1.0</version>
</dependency>
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>jstl</artifactId>
<version>1.2</version>
</dependency>
<dependency>
<groupId>javax.servlet.jsp</groupId>
<artifactId>javax.servlet.jsp-api</artifactId>
<version>2.3.1</version>
</dependency>
</dependencies>
<build>
<pluginManagement>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.2</version>
<configuration>
<source>1.6</source>
<target>1.6</target>
</configuration>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-war-plugin</artifactId>
<version>2.4</version>
<configuration>
<warSourceDirectory>src/main/webapp</warSourceDirectory>
<warName>Spring4MVCContentNegotiatingViewResolverExample</warName>
<failOnMissingWebXml>false</failOnMissingWebXml>
</configuration>
</plugin>
</plugins>
</pluginManagement>
<finalName>Spring4MVCContentNegotiatingViewResolverExample</finalName>
</build>
</project>
spring-oxm 支持 XML 格式的输出 (使用 JAXB2).jackson-databind & jackson-annotations 提供JSON格式的输出. itext提供PDF 创建库支持PDF 的输出. Apache POI 帮助创建 XLS 格式的输出
第3步:创建Spring配置类
com.websystique.springmvc.configuration.AppConfig
package com.websystique.springmvc.configuration;
import java.util.ArrayList;
import java.util.List;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.http.MediaType;
import org.springframework.oxm.jaxb.Jaxb2Marshaller;
import org.springframework.web.accept.ContentNegotiationManager;
import org.springframework.web.servlet.ViewResolver;
import org.springframework.web.servlet.config.annotation.ContentNegotiationConfigurer;
import org.springframework.web.servlet.config.annotation.EnableWebMvc;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;
import org.springframework.web.servlet.view.ContentNegotiatingViewResolver;
import org.springframework.web.servlet.view.InternalResourceViewResolver;
import org.springframework.web.servlet.view.JstlView;
import com.websystique.springmvc.model.Pizza;
import com.websystique.springmvc.viewresolver.ExcelViewResolver;
import com.websystique.springmvc.viewresolver.JsonViewResolver;
import com.websystique.springmvc.viewresolver.Jaxb2MarshallingXmlViewResolver;
import com.websystique.springmvc.viewresolver.PdfViewResolver;
@Configuration
@EnableWebMvc
@ComponentScan(basePackages = "com.websystique.springmvc")
public class AppConfig extends WebMvcConfigurerAdapter {
/*
* Configure ContentNegotiationManager
*/
@Override
public void configureContentNegotiation(ContentNegotiationConfigurer configurer) {
configurer.ignoreAcceptHeader(true).defaultContentType(
MediaType.TEXT_HTML);
}
/*
* Configure ContentNegotiatingViewResolver
*/
@Bean
public ViewResolver contentNegotiatingViewResolver(ContentNegotiationManager manager) {
ContentNegotiatingViewResolver resolver = new ContentNegotiatingViewResolver();
resolver.setContentNegotiationManager(manager);
// Define all possible view resolvers
List<ViewResolver> resolvers = new ArrayList<ViewResolver>();
resolvers.add(jaxb2MarshallingXmlViewResolver());
resolvers.add(jsonViewResolver());
resolvers.add(jspViewResolver());
resolvers.add(pdfViewResolver());
resolvers.add(excelViewResolver());
resolver.setViewResolvers(resolvers);
return resolver;
}
/*
* Configure View resolver to provide XML output Uses JAXB2 marshaller to
* marshall/unmarshall POJO's (with JAXB annotations) to XML
*/
@Bean
public ViewResolver jaxb2MarshallingXmlViewResolver() {
Jaxb2Marshaller marshaller = new Jaxb2Marshaller();
marshaller.setClassesToBeBound(Pizza.class);
return new Jaxb2MarshallingXmlViewResolver(marshaller);
}
/*
* Configure View resolver to provide JSON output using JACKSON library to
* convert object in JSON format.
*/
@Bean
public ViewResolver jsonViewResolver() {
return new JsonViewResolver();
}
/*
* Configure View resolver to provide PDF output using lowagie pdf library to
* generate PDF output for an object content
*/
@Bean
public ViewResolver pdfViewResolver() {
return new PdfViewResolver();
}
/*
* Configure View resolver to provide XLS output using Apache POI library to
* generate XLS output for an object content
*/
@Bean
public ViewResolver excelViewResolver() {
return new ExcelViewResolver();
}
/*
* Configure View resolver to provide HTML output This is the default format
* in absence of any type suffix.
*/
@Bean
public ViewResolver jspViewResolver() {
InternalResourceViewResolver viewResolver = new InternalResourceViewResolver();
viewResolver.setViewClass(JstlView.class);
viewResolver.setPrefix("/WEB-INF/views/");
viewResolver.setSuffix(".jsp");
return viewResolver;
}
}
我们详细说说：
第一步创建ContentNegotiationManager用来决定请求的media代理到ContentNegotiationStrategy实例集合.默认PathExtensionContentNegotiationStrategy 被请求 (使用url拓展名 e.g. .xls, .pdf,.json..) ,然后是ParameterContentNegotiationStrategy (使用的请求参数 ‘format=xls’ e.g.), 然后是HeaderContentNegotiationStrategy (使用HTTP Accept Headers)。
public void configureContentNegotiation(ContentNegotiationConfigurer configurer) {
configurer.ignoreAcceptHeader(true).defaultContentType(
MediaType.TEXT_HTML);
}
在我们的例子中我们将使用基于URL拓展名来决定 媒体类型。
如果没有拓展名我们默认用TEXT_HTML 类处理。
也就是说 未知的拓展名类型我们使用jsp 视图解析器处理。
pizza.jsp 将用来做默认的jsp视图解析器
<%@ page language="java" contentType="text/html; charset=ISO-8859-1" pageEncoding="ISO-8859-1"%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Pizza JSP View</title>
</head>
<body>
<table border="1">
<tr>
<td>NAME</td>
<td>Flavor</td>
<td>Toppings</td>
</tr>
<tr>
<td>${pizza.name}</td>
<td>${pizza.flavor}</td>
<td>
<c:forEach var="item" items="${pizza.toppings}">
<c:out value="${item}"/>
</c:forEach>
</td>
</tr>
</table>
</body>
</html>
下一步配置: ContentNegotaionViewResolver
public ViewResolver contentNegotiatingViewResolver(ContentNegotiationManager manager) {
ContentNegotiatingViewResolver resolver = new ContentNegotiatingViewResolver();
resolver.setContentNegotiationManager(manager);
// Define all possible view resolvers
List<ViewResolver> resolvers = new ArrayList<ViewResolver>();
resolvers.add(jaxb2MarshallingXmlViewResolver());
resolvers.add(jsonViewResolver());
resolvers.add(jspViewResolver());
resolvers.add(pdfViewResolver());
resolvers.add(excelViewResolver());
resolver.setViewResolvers(resolvers);
return resolver;
}
我们需要设置ContentNegotiationManager 并注入到spring中，不同的解析器响应不同格式的请求。
第4步: 创建不同的视图解析器
XML 视图解析器：
package com.websystique.springmvc.viewresolver;
import java.util.Locale;
import org.springframework.oxm.Marshaller;
import org.springframework.web.servlet.View;
import org.springframework.web.servlet.ViewResolver;
import org.springframework.web.servlet.view.xml.MarshallingView;
public class Jaxb2MarshallingXmlViewResolver implements ViewResolver {
private Marshaller marshaller;
public Jaxb2MarshallingXmlViewResolver(Marshaller marshaller) {
this.marshaller = marshaller;
}
@Override
public View resolveViewName(String viewName, Locale locale) throws Exception {
MarshallingView view = new MarshallingView();
view.setMarshaller(marshaller);
return view;
}
}
产生XML的注解
com.websystique.springmvc.model.Pizza
package com.websystique.springmvc.model;
import java.util.ArrayList;
import java.util.List;
import javax.xml.bind.annotation.XmlElement;
import javax.xml.bind.annotation.XmlRootElement;
@XmlRootElement(name = "pizza")
public class Pizza {
private String name;
private String flavor;
private List<String> toppings = new ArrayList<String>();
public Pizza(){
}
public Pizza(String name){
this.name = name;
this.flavor = "spicy";
this.toppings.add("Cheese");
this.toppings.add("bakon");
}
@XmlElement
public void setName(String name) {
this.name = name;
}
public String getName() {
return name;
}
@XmlElement
public void setFlavor(String flavor) {
this.flavor = flavor;
}
public String getFlavor() {
return flavor;
}
public List<String> getToppings() {
return toppings;
}
@XmlElement
public void setToppings(List<String> toppings) {
this.toppings = toppings;
}
}
JSON视图解析器
使用 Spring MappingJackson2JsonView 获取视图将POJO转换为JSON
com.websystique.springmvc.viewresolver.JsonViewResolver
package com.websystique.springmvc.viewresolver;
import java.util.Locale;
import org.springframework.web.servlet.View;
import org.springframework.web.servlet.ViewResolver;
import org.springframework.web.servlet.view.json.MappingJackson2JsonView;
public class JsonViewResolver implements ViewResolver{
@Override
public View resolveViewName(String viewName, Locale locale) throws Exception {
MappingJackson2JsonView view = new MappingJackson2JsonView();
view.setPrettyPrint(true);
return view;
}
}
pdf视图解析器
此视图解析器是使用 lowagie itext 库来实际输出PDF的。
实际视图拓展自Spring AbstractPdfView，它使用的就是itext库。
com.websystique.springmvc.viewresolver.PdfView
package com.websystique.springmvc.viewresolver;
import java.awt.Color;
import java.util.Map;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.springframework.web.servlet.view.document.AbstractPdfView;
import com.lowagie.text.Document;
import com.lowagie.text.Element;
import com.lowagie.text.pdf.PdfPTable;
import com.lowagie.text.pdf.PdfWriter;
import com.websystique.springmvc.model.Pizza;
public class PdfView extends AbstractPdfView {
@Override
protected void buildPdfDocument(Map<String, Object> model,
Document document, PdfWriter writer, HttpServletRequest request,
HttpServletResponse response) throws Exception {
Pizza pizza = (Pizza) model.get("pizza");
PdfPTable table = new PdfPTable(3);
table.getDefaultCell().setHorizontalAlignment(Element.ALIGN_CENTER);
table.getDefaultCell().setVerticalAlignment(Element.ALIGN_MIDDLE);
table.getDefaultCell().setBackgroundColor(Color.lightGray);
table.addCell("Name");
table.addCell("Flavor");
table.addCell("Toppings");
table.addCell(pizza.getName());
table.addCell(pizza.getFlavor());
StringBuffer toppings = new StringBuffer("");
for (String topping : pizza.getToppings()) {
toppings.append(topping);
toppings.append(" ");
}
table.addCell(toppings.toString());
document.add(table);
}
}
com.websystique.springmvc.viewresolver.PdfViewResolver
package com.websystique.springmvc.viewresolver;
import java.util.Locale;
import org.springframework.web.servlet.View;
import org.springframework.web.servlet.ViewResolver;
public class PdfViewResolver implements ViewResolver{
@Override
public View resolveViewName(String viewName, Locale locale) throws Exception {
PdfView view = new PdfView();
return view;
}
}
XLS视图解析器：
使用 Apache POI库产生XLS输出。拓展自Spring AbstractExcelView ,它本身内部使用的就是 Apache POI库。
com.websystique.springmvc.viewresolver.ExcelView
package com.websystique.springmvc.viewresolver;
import java.util.Map;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.CellStyle;
import org.apache.poi.ss.usermodel.IndexedColors;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Sheet;
import org.springframework.web.servlet.view.document.AbstractExcelView;
import com.websystique.springmvc.model.Pizza;
public class ExcelView extends AbstractExcelView {
@Override
protected void buildExcelDocument(Map<String, Object> model,
HSSFWorkbook workbook, HttpServletRequest request,
HttpServletResponse response) throws Exception {
Pizza pizza = (Pizza) model.get("pizza");
Sheet sheet = workbook.createSheet("sheet 1");
CellStyle style = workbook.createCellStyle();
style.setFillForegroundColor(IndexedColors.GREY_40_PERCENT.index);
style.setFillPattern(CellStyle.SOLID_FOREGROUND);
style.setAlignment(CellStyle.ALIGN_CENTER);
Row row = null;
Cell cell = null;
int rowCount = 0;
int colCount = 0;
// Create header cells
row = sheet.createRow(rowCount++);
cell = row.createCell(colCount++);
cell.setCellStyle(style);
cell.setCellValue("Name");
cell = row.createCell(colCount++);
cell.setCellStyle(style);
cell.setCellValue("Flavor");
cell = row.createCell(colCount++);
cell.setCellStyle(style);
cell.setCellValue("Toppings");
// Create data cells
row = sheet.createRow(rowCount++);
colCount = 0;
row.createCell(colCount++).setCellValue(pizza.getName());
row.createCell(colCount++).setCellValue(pizza.getFlavor());
StringBuffer toppings = new StringBuffer("");
for (String topping : pizza.getToppings()) {
toppings.append(topping);
toppings.append(" ");
}
row.createCell(colCount++).setCellValue(toppings.toString());
for (int i = 0; i < 3; i++)
sheet.autoSizeColumn(i, true);
}
}
com.websystique.springmvc.viewresolver.ExcelViewResolver
package com.websystique.springmvc.viewresolver;
import java.util.Locale;
import org.springframework.web.servlet.View;
import org.springframework.web.servlet.ViewResolver;
public class ExcelViewResolver implements ViewResolver{
@Override
public View resolveViewName(String viewName, Locale locale) throws Exception {
ExcelView view = new ExcelView();
return view;
}
}
第5步: 创建控制器类
com.websystique.springmvc.controller.AppController
package com.websystique.springmvc.controller;
import org.springframework.stereotype.Controller;
import org.springframework.ui.ModelMap;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import com.websystique.springmvc.model.Pizza;
@Controller
public class AppController {
@RequestMapping(value="/pizzavalley/{pizzaName}", method = RequestMethod.GET)
public String getPizza(@PathVariable String pizzaName, ModelMap model) {
Pizza pizza = new Pizza(pizzaName);
model.addAttribute("pizza", pizza);
return "pizza";
}
}
第6步:创建初始化类
com.websystique.springmvc.configuration.AppInitializer
package com.websystique.springmvc.configuration;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.ServletRegistration;
import org.springframework.web.WebApplicationInitializer;
import org.springframework.web.context.support.AnnotationConfigWebApplicationContext;
import org.springframework.web.servlet.DispatcherServlet;
public class AppInitializer implements WebApplicationInitializer {
public void onStartup(ServletContext container) throws ServletException {
AnnotationConfigWebApplicationContext ctx = new AnnotationConfigWebApplicationContext();
ctx.register(AppConfig.class);
ctx.setServletContext(container);
ServletRegistration.Dynamic servlet = container.addServlet(
"dispatcher", new DispatcherServlet(ctx));
servlet.setLoadOnStartup(1);
servlet.addMapping("/");
}
}
可简化为下面的类：
package com.websystique.springmvc.configuration;
import org.springframework.web.servlet.support.AbstractAnnotationConfigDispatcherServletInitializer;
public class AppInitializer extends AbstractAnnotationConfigDispatcherServletInitializer {
@Override
protected Class<?>[] getRootConfigClasses() {
return new Class[] { AppConfig.class };
}
@Override
protected Class<?>[] getServletConfigClasses() {
return null;
}
@Override
protected String[] getServletMappings() {
return new String[] { "/" };
}
}
Step 7:创建和发布
在tomcat中发布
下面截图是根据url拓展名来作不同的响应
[源码下载地址:http://websystique.com/?smd_process_download=1&download_id=772]