针对新的 Spring Validator 类运行单元测试时，我不断收到“NotReadablePropertyException”

Question

我正在通过 Spring MVC 创建一个基本的登录页面。到目前为止，我已经创建了以下内容：

• 一个简单的“登录”POJO 类
• 实现 spring 接口的“LoginValidator”类：org.springframework.validation.Validator
• 'LoginValidatorTests' 类

我的单元测试失败，出现以下异常：

org.springframework.beans.NotReadablePropertyException: Invalid property 'login' of bean class [springapp.service.LoginValidator]: Bean property 'login' is not readable or has an invalid getter method: Does the return type of the getter match the parameter type of the setter?
    at org.springframework.beans.BeanWrapperImpl.getPropertyValue(BeanWrapperImpl.java:707)
    at org.springframework.beans.BeanWrapperImpl.getPropertyValue(BeanWrapperImpl.java:699)
    at org.springframework.validation.AbstractPropertyBindingResult.getActualFieldValue(AbstractPropertyBindingResult.java:99)
    at org.springframework.validation.AbstractBindingResult.rejectValue(AbstractBindingResult.java:105)
    at springapp.service.LoginValidator.validateUsername(LoginValidator.java:44)
    at springapp.service.LoginValidator.validate(LoginValidator.java:27)
    at springapp.service.LoginValidatorTests.testEmptyUsernameAndPassword(LoginValidatorTests.java:28)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    at junit.framework.TestCase.runTest(TestCase.java:164)
    at junit.framework.TestCase.runBare(TestCase.java:130)
    at junit.framework.TestResult$1.protect(TestResult.java:106)
    at junit.framework.TestResult.runProtected(TestResult.java:124)
    at junit.framework.TestResult.run(TestResult.java:109)
    at junit.framework.TestCase.run(TestCase.java:120)
    at org.eclipse.jdt.internal.junit.runner.junit3.JUnit3TestReference.run(JUnit3TestReference.java:130)
    at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)

下面的代码截图。

1. 登录.java：

   包 springapp.service;

   import org.apache.commons.logging.Log;
   import org.apache.commons.logging.LogFactory;
   
   
   public class Login{
   
       /** Logger for this class and subclasses */
       protected final Log logger = LogFactory.getLog(getClass());
   
       private String username;
       private String password;
   
       public void setUsername(String username){
           this.username = username;
       }
   
       public String getUsername(){
           return username;
       }
   
       public void setPassword(String password){
           this.password = password;
       }
   
       public String getPassword(){
           return password;
       }
   
   }
   

2. 登录验证器.java

   package springapp.service;
   
   import org.springframework.validation.Validator;
   import org.springframework.validation.Errors;
   
   import org.apache.commons.logging.Log;
   import org.apache.commons.logging.LogFactory;
   
   //import springapp.domain.Login;
   
   public class LoginValidator implements Validator {
   
       /** Logger for this class and subclasses */
       protected final Log logger = LogFactory.getLog(getClass());
   
       public boolean supports(Class clazz) {
           return Login.class.equals(clazz);
       }
   
       public void validate(Object obj, Errors errors) {
           Login login = (Login) obj;
   
           if (login == null) {
               errors.rejectValue("login", "error.username-and-password-required", null, "Value required.");
           }
           //validate username
           validateUsername(login, errors);
   
           //if no errors, validate password
           if (!errors.hasErrors()){
               validatePassword(login, errors);
           }           
       }
   
       private boolean validateUsername(Login login, Errors errors){
           String username = login.getUsername();
   
           if (username == null || username.length() == 0){
               errors.rejectValue("login", "error.username-required", null, "Value required.");
               return false;
           }
   
           if (username != "admin") {
               errors.rejectValue("login", "error.username-not-found", null, "Value required.");
               return false;
           }
   
           return true;
       }
   
       private boolean validatePassword(Login login, Errors errors){
           String password = login.getPassword();
   
           if (password == null || password.length() == 0){
               errors.rejectValue("login", "error.password-required", null, "Value required.");
               return false;
           }
   
           if (password != "admin") {
               errors.rejectValue("login", "error.password-invalid", null, "Value required.");
               return false;
           }
   
           return true;        
       }   
   
   }
   

3. 登录验证器测试.java。运行单元测试“testEmptyUsernameAndPassword”时，出现异常：

   package springapp.service;
   
   import junit.framework.TestCase;
   
   import springapp.service.LoginValidator;
   
   import org.apache.commons.logging.Log;
   import org.apache.commons.logging.LogFactory;
   
   import org.springframework.validation.BeanPropertyBindingResult;
   import org.springframework.validation.Validator;
   import org.springframework.validation.Errors;
   
   public class LoginValidatorTests extends TestCase {
   
       protected final Log logger = LogFactory.getLog(getClass());
       private LoginValidator loginValidator = new LoginValidator();
       private Login login= new Login();
       private Errors errors = new BeanPropertyBindingResult(loginValidator, "loginValidator");
   
       public void testEmptyUsernameAndPassword(){
           login.setPassword("ee");
           login.setUsername("ee");
           loginValidator.validate(login, errors);
   
           assertTrue(errors.hasErrors());
           //assertTrue(errors.getFieldError().toString().contains("error.username-and-password-required"));
       }
   
       public void testEmptyUsernameOnly(){
   
       }
   
       public void testEmptyPasswordOnly(){
   
       }
   
       public void testInvalidUsername(){
   
       }
   
       public void testInvalidPassword(){
   
       }
   }
   

Answer 1

第一的

private Errors errors = new BeanPropertyBindingResult(loginValidator, "loginValidator");

应该

private Errors errors = new BeanPropertyBindingResult(login, "login" /* or whatever name */);

否则你的目标对象Errors是LoginValidator对象而不是你的Login对象。

注意javadoc Errors#rejectValue(..)

field - 字段名称（可能为 null 或空字符串）

所以你在这里指定的是什么

errors.rejectValue("login", "error.username-required", null, "Value required.");

该值login 实际上用作目标对象的类的字段名称。但是你的Login班级和你的LoginValidator班级都没有这样的领域。您应该在适当的地方使用username或password。