custom class validation (#1832)

* custom class validation

* formatting

spring-mvc-java/src/main/java/com/baeldung/customvalidator/FieldsValueMatch.java

@@ -0,0 +1,31 @@
+package com.baeldung.customvalidator;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+import javax.validation.Constraint;
+import javax.validation.Payload;
+
+@Constraint(validatedBy = FieldsValueMatchValidator.class)
+@Target({ ElementType.TYPE })
+@Retention(RetentionPolicy.RUNTIME)
+public @interface FieldsValueMatch {
+
+    String message() default "Fields values don't match!";
+
+    Class<?>[] groups() default {};
+
+    Class<? extends Payload>[] payload() default {};
+
+    String field();
+
+    String fieldMatch();
+
+    @Target({ ElementType.TYPE })
+    @Retention(RetentionPolicy.RUNTIME)
+    @interface List {
+        FieldsValueMatch[] value();
+    }
+}

spring-mvc-java/src/main/java/com/baeldung/customvalidator/FieldsValueMatchValidator.java

@@ -0,0 +1,31 @@
+package com.baeldung.customvalidator;
+
+import javax.validation.ConstraintValidator;
+import javax.validation.ConstraintValidatorContext;
+
+import org.springframework.beans.BeanWrapperImpl;
+
+public class FieldsValueMatchValidator implements ConstraintValidator<FieldsValueMatch, Object> {
+
+    private String field;
+    private String fieldMatch;
+
+    public void initialize(FieldsValueMatch constraintAnnotation) {
+        this.field = constraintAnnotation.field();
+        this.fieldMatch = constraintAnnotation.fieldMatch();
+    }
+
+    public boolean isValid(Object value, ConstraintValidatorContext context) {
+
+        Object fieldValue = new BeanWrapperImpl(value).getPropertyValue(field);
+        Object fieldMatchValue = new BeanWrapperImpl(value).getPropertyValue(fieldMatch);
+        
+        if (fieldValue != null) {
+            return fieldValue.equals(fieldMatchValue);
+        } else {
+            return fieldMatchValue == null;
+        }
+
+    }
+
+}

spring-mvc-java/src/main/java/com/baeldung/model/NewUserForm.java

@@ -0,0 +1,58 @@
+package com.baeldung.model;
+
+import com.baeldung.customvalidator.FieldsValueMatch;
+
+@FieldsValueMatch.List({ 
+    @FieldsValueMatch(field = "password", fieldMatch = "verifyPassword", message = "Passwords do not match!"), 
+    @FieldsValueMatch(field = "email", fieldMatch = "verifyEmail", message = "Email addresses do not match!")
+})
+public class NewUserForm {
+    private String email;
+    private String verifyEmail;
+    private String password;
+    private String verifyPassword;
+
+    public NewUserForm() {
+    }
+
+    public NewUserForm(String email, String verifyEmail, String password, String verifyPassword) {
+        super();
+        this.email = email;
+        this.verifyEmail = verifyEmail;
+        this.password = password;
+        this.verifyPassword = verifyPassword;
+    }
+
+    public String getEmail() {
+        return email;
+    }
+
+    public void setEmail(String email) {
+        this.email = email;
+    }
+
+    public String getVerifyEmail() {
+        return verifyEmail;
+    }
+
+    public void setVerifyEmail(String verifyEmail) {
+        this.verifyEmail = verifyEmail;
+    }
+
+    public String getPassword() {
+        return password;
+    }
+
+    public void setPassword(String password) {
+        this.password = password;
+    }
+
+    public String getVerifyPassword() {
+        return verifyPassword;
+    }
+
+    public void setVerifyPassword(String verifyPassword) {
+        this.verifyPassword = verifyPassword;
+    }
+
+}

spring-mvc-java/src/main/java/com/baeldung/web/controller/NewUserController.java

@@ -0,0 +1,31 @@
+package com.baeldung.web.controller;
+
+import javax.validation.Valid;
+
+import org.springframework.stereotype.Controller;
+import org.springframework.ui.Model;
+import org.springframework.validation.BindingResult;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PostMapping;
+
+import com.baeldung.model.NewUserForm;
+
+@Controller
+public class NewUserController {
+
+    @GetMapping("/user")
+    public String loadFormPage(Model model) {
+        model.addAttribute("newUserForm", new NewUserForm());
+        return "userHome";
+    }
+
+    @PostMapping("/user")
+    public String submitForm(@Valid NewUserForm newUserForm, BindingResult result, Model model) {
+        if (result.hasErrors()) {
+            return "userHome";
+        }
+
+        model.addAttribute("message", "Valid form");
+        return "userHome";
+    }
+}

spring-mvc-java/src/main/java/com/baeldung/web/controller/ValidatedPhoneController.java

@@ -6,12 +6,10 @@ import org.springframework.ui.Model;
 import org.springframework.validation.BindingResult;
 import org.springframework.web.bind.annotation.GetMapping;
 import org.springframework.web.bind.annotation.PostMapping;
-import org.springframework.web.servlet.config.annotation.EnableWebMvc;
 
 import javax.validation.Valid;
 
 @Controller
-@EnableWebMvc
 public class ValidatedPhoneController {
 
     @GetMapping("/validatePhone")

spring-mvc-java/src/test/java/com/baeldung/web/controller/ClassValidationMvcTest.java

@@ -0,0 +1,51 @@
+package com.baeldung.web.controller;
+
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
+import static org.springframework.test.web.servlet.result.MockMvcResultHandlers.print;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.model;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.view;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.springframework.http.MediaType;
+import org.springframework.test.web.servlet.MockMvc;
+import org.springframework.test.web.servlet.request.MockMvcRequestBuilders;
+import org.springframework.test.web.servlet.setup.MockMvcBuilders;
+
+public class ClassValidationMvcTest {
+  private MockMvc mockMvc;
+    
+    @Before
+    public void setup(){
+        this.mockMvc = MockMvcBuilders.standaloneSetup(new NewUserController()).build();
+    }
+    
+    @Test
+    public void givenMatchingEmailPassword_whenPostNewUserForm_thenOk() throws Exception {
+        this.mockMvc.perform(MockMvcRequestBuilders.post("/user")
+                .accept(MediaType.TEXT_HTML)
+                .param("email", "john@yahoo.com")
+                .param("verifyEmail", "john@yahoo.com")
+                .param("password", "pass")
+                .param("verifyPassword", "pass"))
+                .andExpect(model().attribute("message", "Valid form"))
+                .andExpect(view().name("userHome"))
+                .andExpect(status().isOk())
+                .andDo(print());
+    }
+    
+    @Test
+    public void givenNotMatchingEmailPassword_whenPostNewUserForm_thenOk() throws Exception {
+        this.mockMvc.perform(MockMvcRequestBuilders.post("/user")
+                .accept(MediaType.TEXT_HTML)
+                .param("email", "john@yahoo.com")
+                .param("verifyEmail", "john@yahoo.commmm")
+                .param("password", "pass")
+                .param("verifyPassword", "passsss"))
+                .andExpect(model().errorCount(2))
+                .andExpect(view().name("userHome"))
+                .andExpect(status().isOk())
+                .andDo(print());
+    }
+}