Spring in Action 之WEB篇

Spring in Action 之WEB篇

配置DispatcherServlet

使用JavaConfig的方式创建DispatcherServlet:

import org.springframework.web.servlet.support.AbstractAnnotationConfigDispatcherServletInitializer;
import spittr.web.WebConfig;

public class SpitterWebInitializer extends AbstractAnnotationConfigDispatcherServletInitializer {

@Override
protected Class<?>[] getRootConfigClasses() {
return new Class<?>[]{RootConfig.class};
}

@Override
protected Class<?>[] getServletConfigClasses() {
return new Class<?>[]{WebConfig.class};
}

@Override
protected String[] getServletMappings() {
return new String[]{"/"};
}

}

注意:Spring的应用上下文会处在应用程序的Servlet上下文之中。

在Servlet3.0容器中，容器会在类路径中查找实现javax.servlet.ServletContainerInitializer接口的类，如果能发现，就会用它来配置Servlet容器。Spring提供了这个接口的实现，名为SpringServletContainerInitializer，这个类反过来又会查找实现实现WebApplicationInitializer的类并将配置的任务交给他们来完成。Spring3.2引入了一个便利的WebApplicationInitializer基础实现，也就是AbstractAnnotationConfigDispatcherServletInitializer。当部署到Servlet3.0容器中的时候，容器会自动发现它，并用它来配置Servlet上下文。

实际上，AbstractAnnotationConfigDispatcherServletInitializer会同时创建DispatcherServlet和ContextLoaderListener。

启动Spring MVC

以前我们使用< mvc:annotation-driven>启动注解驱动的SpringMVC.

如果我们没有配置视图解析器，Spring会默认使用BeanNameViewResolver，这个视图解析器会查找ID与视图名称匹配的bean，并且查找的bean要实现View接口，它以这种方式来解析视图。

WebConfig:

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.ViewResolver;
import org.springframework.web.servlet.config.annotation.DefaultServletHandlerConfigurer;
import org.springframework.web.servlet.config.annotation.EnableWebMvc;
import org.springframework.web.servlet.config.annotation.ResourceHandlerRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;
import org.springframework.web.servlet.view.InternalResourceViewResolver;

@Configuration
@EnableWebMvc
@ComponentScan("spittr.web")
public class WebConfig extends WebMvcConfigurerAdapter {

@Bean
public ViewResolver viewResolver() {
InternalResourceViewResolver resolver = new InternalResourceViewResolver();
resolver.setPrefix("/WEB-INF/views/");
resolver.setSuffix(".jsp");
return resolver;
}

@Override
public void configureDefaultServletHandling(DefaultServletHandlerConfigurer configurer) {
configurer.enable();
}

@Override
public void addResourceHandlers(ResourceHandlerRegistry registry) {
super.addResourceHandlers(registry);
}

}

注意点：通过调用DefaultServletHandlerConfigurer的enable()方法，我们要求DispatcherServlet将对静态资源的请求转发到Servlet容器中默认的Servlet上。

在SpringMVC中，控制器只是方法上添加了@Controller注解的类，这个注解声明了他们所要处理的请求。

针对Controller的测试：

import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;
import static org.springframework.web.bind.annotation.RequestMethod.GET;

@Controller
@RequestMapping("/")
public class HomeController {

@RequestMapping(method = GET)
public String home(Model model) {
return "home";
}

}

import org.junit.Test;
import org.springframework.test.web.servlet.MockMvc;

import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.view;
import static org.springframework.test.web.servlet.setup.MockMvcBuilders.standaloneSetup;

public class HomeControllerTest {

@Test
public void testHomePage() throws Exception {
HomeController controller = new HomeController();
MockMvc mockMvc = standaloneSetup(controller).build();
mockMvc.perform(get("/")).andExpect(view().name("home"));
}

}

高阶controller测试:

import org.junit.Test;
import org.springframework.test.web.servlet.MockMvc;
i
4000
mport org.springframework.web.servlet.view.InternalResourceView;
import spittr.Spittle;
import spittr.data.SpittleRepository;

import java.util.ArrayList;
import java.util.Date;
import java.util.List;

import static org.hamcrest.Matchers.hasItems;
import static org.mockito.Mockito.atLeastOnce;
import static org.mockito.Mockito.mock;
import static org.mockito.Mockito.verify;
import static org.mockito.Mockito.when;
import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.post;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.model;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.redirectedUrl;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.view;
import static org.springframework.test.web.servlet.setup.MockMvcBuilders.standaloneSetup;

public class SpittleControllerTest {

@Test
public void houldShowRecentSpittles() throws Exception {
List<Spittle> expectedSpittles = createSpittleList(20);
SpittleRepository mockRepository = mock(SpittleRepository.class);
when(mockRepository.findSpittles(Long.MAX_VALUE, 20)).thenReturn(expectedSpittles);

SpittleController controller = new SpittleController(mockRepository);
MockMvc mockMvc = standaloneSetup(controller)
.setSingleView(new InternalResourceView("/WEB-INF/views/spittles.jsp"))
.build();

mockMvc.perform(get("/spittles"))
.andExpect(view().name("spittles"))
.andExpect(model().attributeExists("spittleList"))
.andExpect(model().attribute("spittleList", hasItems(expectedSpittles.toArray())));
}

@Test
public void shouldShowPagedSpittles() throws Exception {
List<Spittle> expectedSpittles = createSpittleList(50);
SpittleRepository mockRepository = mock(SpittleRepository.class);
when(mockRepository.findSpittles(238900, 50))
.thenReturn(expectedSpittles);

SpittleController controller = new SpittleController(mockRepository);
MockMvc mockMvc = standaloneSetup(controller)
.setSingleView(new InternalResourceView("/WEB-INF/views/spittles.jsp"))
.build();

mockMvc.perform(get("/spittles?max=238900&count=50"))
.andExpect(view().name("spittles"))
.andExpect(model().attributeExists("spittleList"))
.andExpect(model().attribute("spittleList",
hasItems(expectedSpittles.toArray())));
}

@Test
public void testSpittle() throws Exception {
Spittle expectedSpittle = new Spittle("Hello", new Date());
SpittleRepository mockRepository = mock(SpittleRepository.class);
when(mockRepository.findOne(12345)).thenReturn(expectedSpittle);

SpittleController controller = new SpittleController(mockRepository);
MockMvc mockMvc = standaloneSetup(controller).build();

mockMvc.perform(get("/spittles/12345"))
.andExpect(view().name("spittle"))
.andExpect(model().attributeExists("spittle"))
.andExpect(model().attribute("spittle", expectedSpittle));
}

@Test
public void saveSpittle() throws Exception {
SpittleRepository mockRepository = mock(SpittleRepository.class);
SpittleController controller = new SpittleController(mockRepository);
MockMvc mockMvc = standaloneSetup(controller).build();

mockMvc.perform(post("/spittles")
.param("message", "Hello World") // this works, but isn't really testing what really happens
.param("longitude", "-81.5811668")
.param("latitude", "28.4159649")
)
.andExpect(redirectedUrl("/spittles"));

verify(mockRepository, atLeastOnce()).save(new Spittle(null, "Hello World", new Date(), -81.5811668, 28.4159649));
}

private List<Spittle> createSpittleList(int count) {
List<Spittle> spittles = new ArrayList<>();
for (int i = 0; i < count; i++) {
spittles.add(new Spittle("Spittle " + i, new Date()));
}
return spittles;
}
}

Spring MVC允许以多种方式将客户端中的数据传送到控制器的处理器方法中，包括:

查询参数（Query Parameter）

表单参数（Form Parameter）

路径变量（Path Variable）

Controller代码样例:

@Controller
@RequestMapping("/spittles")
public class SpittleController {

private static final String MAX_LONG_AS_STRING = "9223372036854775807";

private SpittleRepository spittleRepository;

@Autowired
public SpittleController(SpittleRepository spittleRepository) {
this.spittleRepository = spittleRepository;
}
// 查询参数
@RequestMapping(method = RequestMethod.GET)
public List<Spittle> spittles(
@RequestParam(value = "max", defaultValue = MAX_LONG_AS_STRING) long max,
@RequestParam(value = "count", defaultValue = "20") int count) {
return spittleRepository.findSpittles(max, count);
}
// 路径变量
@RequestMapping(value = "/{spittleId}", method = RequestMethod.GET)
public String spittle(@PathVariable("spittleId") long spittleId, Model model) {
model.addAttribute(spittleRepository.findOne(spittleId));
return "spittle";
}

@RequestMapping(method = RequestMethod.POST)
public String saveSpittle(SpittleForm form, Model model) throws Exception {
spittleRepository.save(new Spittle(null, form.getMessage(), new Date(), form.getLongitude(), form.getLatitude()));
return "redirect:/spittles";
}

}

校验对象:

import javax.validation.constraints.NotNull;
import javax.validation.constraints.Size;

import org.apache.commons.lang3.builder.EqualsBuilder;
import org.apache.commons.lang3.builder.HashCodeBuilder;
import org.hibernate.validator.constraints.Email;

public class Spitter {

private Long id;

@NotNull
@Size(min=5, max=16)
private String username;

@NotNull
@Size(min=5, max=25)
private String password;

@NotNull
@Size(min=2, max=30)
private String firstName;

@NotNull
@Size(min=2, max=30)
private String lastName;

@NotNull
@Email
private String email;

public Spitter() {}

public Spitter(String username, String password, String firstName, String lastName, String email) {
this(null, username, password, firstName, lastName, email);
}

public Spitter(Long id, String username, String password, String firstName, String lastName, String email) {
this.id = id;
this.username = username;
this.password = password;
this.firstName = firstName;
this.lastName = lastName;
this.email = email;
}

public String getUsername() {
return username;
}

public void setUsername(String username) {
this.username = username;
}

public String getPassword() {
return password;
}

public void setPassword(String password) {
this.password = password;
}

public Long getId() {
return id;
}

public void setId(Long id) {
this.id = id;
}

public String getFirstName() {
return firstName;
}

public void setFirstName(String firstName) {
this.firstName = firstName;
}

public String getLastName() {
return lastName;
}

public void setLastName(String lastName) {
this.lastName = lastName;
}

public<
a9b6
/span> String getEmail() {
return email;
}

public void setEmail(String email) {
this.email = email;
}

@Override
public boolean equals(Object that) {
return EqualsBuilder.reflectionEquals(this, that, "firstName", "lastName", "username", "password", "email");
}

@Override
public int hashCode() {
return HashCodeBuilder.reflectionHashCode(this, "firstName", "lastName", "username", "password", "email");
}

}

对应注册校验的controller:

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.validation.Errors;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import spittr.Spitter;
import spittr.data.SpitterRepository;

import javax.validation.Valid;

import static org.springframework.web.bind.annotation.RequestMethod.GET;
import static org.springframework.web.bind.annotation.RequestMethod.POST;

@Controller
@RequestMapping("/spitter")
public class SpitterController {

private SpitterRepository spitterRepository;

@Autowired
public SpitterController(SpitterRepository spitterRepository) {
this.spitterRepository = spitterRepository;
}

@RequestMapping(value = "/register", method = GET)
public String showRegistrationForm() {
return "registerForm";
}

@RequestMapping(value = "/register", method = POST)
public String processRegistration(@Valid Spitter spitter, Errors errors) {
if (errors.hasErrors()) {
return "registerForm";
}

spitterRepository.save(spitter);
return "redirect:/spitter/" + spitter.getUsername();
}

@RequestMapping(value = "/{username}", method = GET)
public String showSpitterProfile(@PathVariable String username, Model model) {
Spitter spitter = spitterRepository.findByUsername(username);
model.addAttribute(spitter);
return "profile";
}

}

注意：Errors参数要紧跟在带有@Valid注解的参数后面，@Valid注解所标注的就是要校验的参数。

校验相关注解：

Annotation	Description
@AssertFalse	The annotated element must be a Boolean type and be false.
@AssertTrue	The annotated element must be a Boolean type and be true.
@DecimalMax	The annotated element must be a number whose value is less than or equal toa given BigDecimalString value.
@DecimalMin	The annotated element must be a number whose value is greater than orequal to a given BigDecimalString value.
@Digits	The annotated element must be a number whose value has a specified num-ber of digits.
@Future	The value of the annotated element must be a date in the future.
@Max	The annotated element must be a number whose value is less than or equal toa given value.
@Min	The annotated element must be a number whose value is greater than orequal to a given value.
@NotNull	The value of the annotated element must not be null.
@Null	The value of the annotated element must be null.
@Past	The value of the annotated element must be a date in the past.
@Pattern	The value of the annotated element must match a given regular expression.
@Size	The value of the annotated element must be either a String, a collection, oran array whose length fits within the given range.