下面提供一種springmvc的校驗方案，一般沒有校驗或者手動寫validator的話都要寫好多代碼好多if判斷，使用JSR-303規範校驗隻需要在Pojo字段上加上相應的注解就可以實作校驗了
1.依賴的jar包，我直接貼pom了
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<spring.version>4.1.1.RELEASE</spring.version>
</properties>
<dependencies>
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-core</artifactId>
<version>2.4.0</version>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-databind</artifactId>
<version>2.4.0</version>
</dependency>
<dependency>
<groupId>commons-fileupload</groupId>
<artifactId>commons-fileupload</artifactId>
<version>1.3.1</version>
</dependency>
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>javax.servlet-api</artifactId>
<version>3.1.0</version>
</dependency>
<dependency>
<groupId>javax.validation</groupId>
<artifactId>validation-api</artifactId>
<version>1.1.0.Final</version>
</dependency>
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-validator</artifactId>
<version>5.1.3.Final</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-orm</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-web</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-test</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-log4j12</artifactId>
<version>1.7.7</version>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.11</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.aspectj</groupId>
<artifactId>aspectjweaver</artifactId>
<version>1.8.4</version>
</dependency>
<dependency>
<groupId>javax.el</groupId>
<artifactId>javax.el-api</artifactId>
<version>3.0.0</version>
</dependency>
</dependencies>
2.springmvc配置
<?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:tx="http://www.springframework.org/schema/tx"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:mvc="http://www.springframework.org/schema/mvc"
xmlns:aop="http://www.springframework.org/schema/aop"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
http://www.springframework.org/schema/tx
http://www.springframework.org/schema/tx/spring-tx-3.0.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.0.xsd
http://www.springframework.org/schema/mvc
http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd
http://www.springframework.org/schema/aop
http://www.springframework.org/schema/aop/spring-aop.xsd">
<!-- 預設的注解映射的支援 -->
<mvc:annotation-driven/>
<context:annotation-config/>
<aop:aspectj-autoproxy/>
<!-- 自動掃描的包名 -->
<context:component-scan base-package="spring.test.web.controller"/>
<bean id="mappingJacksonHttpMessageConverter" class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter" />
</beans>
3.寫java代碼了
先建一個User類
public class User {
@NotNull
private String username;
@NotNull(message = "密碼不能為空")
private String password;
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;
}
}
然後建一個controller試試
@ResponseBody
@RequestMapping("/test1")
public AjaxResponse validateTest1(@Valid User user, BindingResult result){
AjaxResponse ajaxResponse = new AjaxResponse();
Map<String, Object> map = new HashMap<>();
if(result.hasErrors()){
ajaxResponse.setSuccess(false);
ajaxResponse.setHasErrors(true);
map.put("errors", result.getAllErrors());
}
else {
map.put("now", new Date());
map.put("user", user);
}
ajaxResponse.setData(map);
return ajaxResponse;
}
這個方法第一個參數上加了@Valid标注，第二個參數是必須的而且必須緊跟着@Valid參數之後，校驗結果都在這個result裡面
方法邏輯比較簡單，調用result.hasErrors()看校驗有沒有錯誤，有錯誤的話就把所有的錯誤放進結果傳回給用戶端，如果沒有錯誤就傳回目前時間跟user對象
然後寫個測試方法試試
@Test
public void test1() throws Exception{
this.mockMvc.perform(post("/validator/test1")).andDo(print());
this.mockMvc.perform(post("/validator/test1").param("username", "testusername").param("password", "testpassword")).andDo(print());
}
第一個請求的結果是
{"success":false,"message":null,"hasErrors":true,"data":[{"name":"user","message":"may not be null"},{"name":"user","message":"密碼不能為空"}]}
第二個請求結果是
{"success":true,"message":null,"hasErrors":false,"data":{"now":1420788232169,"user":{"username":"testusername","password":"testpassword"}}}
很明顯第一次請求沒有使用者名和密碼兩個字段校驗都沒有通過，第二次是成功的
用起來還是很簡單的，但是如果我不想每次都在controller方法裡寫if(result.hasErrors())怎麼辦呢，寫個切面，把if寫在切面裡，如果有errors直接就傳回了，不用再執行controller方法了
@Aspect
public class ValidAspect {
@Autowired private Validator validator;
@Around("@annotation(org.springframework.web.bind.annotation.ResponseBody)")
public Object doTest(ProceedingJoinPoint pjp) throws Throwable{
MethodSignature signature = (MethodSignature) pjp.getSignature();
Method method = signature.getMethod();
if(!AjaxResponse.class.equals(method.getReturnType())){
pjp.proceed();
}
Object[] args = pjp.getArgs();
Annotation[][] annotations = method.getParameterAnnotations();
for(int i = 0; i < annotations.length; i++){
if(!hasValidAnnotation(annotations[i])){
continue;
}
if(!(i < annotations.length-1 && args[i+1] instanceof BindingResult)){
//驗證對象後面沒有跟bindingResult,事實上如果沒有應該到不了這一步
continue;
}
BindingResult result = (BindingResult) args[i+1];
if(result.hasErrors()){
AjaxResponse ajaxResponse = new AjaxResponse();
ajaxResponse.setSuccess(false);
ajaxResponse.setHasErrors(true);
ajaxResponse.setData(processErrors(result));
return ajaxResponse;
}
}
return pjp.proceed();
}
private boolean hasValidAnnotation(Annotation[] annotations){
if(annotations == null){
return false;
}
for(Annotation annotation : annotations){
if(annotation instanceof Valid){
return true;
}
}
return false;
}
private List<BindingError> processErrors(BindingResult result){
if(result != null && result.hasErrors()){
List<BindingError> list = new ArrayList<BindingError>();
for(ObjectError error : result.getAllErrors()){
BindingError be = new BindingError();
be.setMessage(error.getDefaultMessage());
be.setName(error.getObjectName());
list.add(be);
}
return list;
}
return null;
}
}
注意要在springmvc配置檔案加一行<bean class="spring.test.web.aop.ValidAspect"/>
然後再寫個方法邏輯跟上面的類似
@ResponseBody
@RequestMapping("/test2")
public AjaxResponse validateTest2(@Valid User user, BindingResult result){
AjaxResponse ajaxResponse = new AjaxResponse();
Map<String, Object> map = new HashMap<>();
map.put("now", new Date());
map.put("user", user);
ajaxResponse.setData(map);
return ajaxResponse;
}
這裡沒有再去判斷hasErrors()了，然後測試一下
寫測試方式試一下
@Test
public void test2() throws Exception{
this.mockMvc.perform(post("/validator/test2")).andDo(print());
this.mockMvc.perform(post("/validator/test2").param("username", "testusername").param("password", "testpassword")).andDo(print());
}
第一個請求結果是
{"success":false,"message":null,"hasErrors":true,"data":[{"name":"user","message":"密碼不能為空"},{"name":"user","message":"may not be null"}]}
第二個請求結果是
{"success":true,"message":null,"hasErrors":false,"data":{"now":1420788479105,"user":{"username":"testusername","password":"testpassword"}}}
效果跟上面是一樣的
當然我這個切面僅僅是個示範，我攔截的是帶有ResponseBody注解的方法，我這些方法會傳回一個統一的格式，如果是要傳回别的視圖就要自己定義注解加其他參數了
JSR-303原生支援的校驗注解也是有限的，如果要實作其他的驗證，可以自己拓展，拓展方法就下次再說了，我也才剛接觸。
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