Refactor ValidationUtils

src/main/java/cc/ryanc/halo/utils/ValidationUtils.java

@@ -1,56 +1,85 @@
 package cc.ryanc.halo.utils;
 
+import org.springframework.lang.NonNull;
+import org.springframework.lang.Nullable;
 import org.springframework.util.CollectionUtils;
 import org.springframework.validation.FieldError;
 
 import javax.validation.ConstraintViolation;
-import java.util.HashMap;
+import javax.validation.ConstraintViolationException;
-import java.util.List;
+import javax.validation.Validation;
-import java.util.Map;
+import javax.validation.Validator;
-import java.util.Set;
+import java.util.*;
 
 /**
- * 有关字段验证的工具类
+ * Object validation utilities.
  *
  * @author johnniang
+ * @data 03/29/19
  */
 public class ValidationUtils {
 
+    private static Validator VALIDATOR;
+
     private ValidationUtils() {
     }
 
+    /**
+     * Gets validator, or create it.
+     *
+     * @return validator
+     */
+    @NonNull
+    public static Validator getValidatorOrCreate() {
+        if (VALIDATOR == null) {
+            synchronized (ValidationUtils.class) {
+                // Init the validation
+                VALIDATOR = Validation.buildDefaultValidatorFactory().getValidator();
+            }
+        }
+
+        return VALIDATOR;
+    }
+
+    /**
+     * Validates bean by hand.
+     *
+     * @param obj    bean to be validated
+     * @param groups validation group
+     * @throws ConstraintViolationException throw if validation failure
+     */
+    public static void validate(Object obj, Class<?>... groups) {
+
+        Validator validator = getValidatorOrCreate();
+
+        // Validate the object
+        Set<ConstraintViolation<Object>> constraintViolations = validator.validate(obj, groups);
+
+        if (!CollectionUtils.isEmpty(constraintViolations)) {
+            // If contain some errors then throw constraint violation exception
+            throw new ConstraintViolationException(constraintViolations);
+        }
+    }
+
+
     /**
      * 将字段验证错误转换为标准的map型，key:value = field:message
      *
      * @param constraintViolations constraint violations(contain error information)
-     * @return 如果返回null则未出现错误
+     * @return error detail map
      */
-    public static Map<String, String> mapWithValidError(Set<ConstraintViolation<Object>> constraintViolations) {
+    @NonNull
-        Map<String, String> errMap = null;
+    public static Map<String, String> mapWithValidError(Set<ConstraintViolation<?>> constraintViolations) {
-        if (!CollectionUtils.isEmpty(constraintViolations)) {
+        if (CollectionUtils.isEmpty(constraintViolations)) {
-            // if not empty
+            return Collections.emptyMap();
-            errMap = new HashMap<>(4);
-            for (ConstraintViolation<Object> constraintViolation : constraintViolations) {
-                errMap.put(constraintViolation.getPropertyPath().toString(), constraintViolation.getMessage());
-            }
         }
-        return errMap;
-    }
 
-    public static String stringWithValidError(Set<ConstraintViolation<?>> violations, boolean allError) {
+        Map<String, String> errMap = new HashMap<>(4);
-        StringBuilder errString = new StringBuilder();
+        // Format the error message
-        if (!CollectionUtils.isEmpty(violations)) {
+        constraintViolations.forEach(
-            for (ConstraintViolation<?> violation : violations) {
+                constraintViolation ->
-                if (errString.length() > 0) {
+                        errMap.put(constraintViolation.getPropertyPath().toString(), constraintViolation.getMessage()));
-                    errString.append(",");
+        return errMap;
-                }
-                errString.append(violation.getMessage());
-                if (!allError && errString.length() > 0) {
-                    return errString.toString();
-                }
-            }
-        }
-        return errString.toString();
     }
 
     /**
@@ -59,35 +88,13 @@ public class ValidationUtils {
      * @param fieldErrors 字段错误组
      * @return 如果返回null，则表示未出现错误
      */
-    public static Map<String, String> mapWithFieldError(List<FieldError> fieldErrors) {
+    public static Map<String, String> mapWithFieldError(@Nullable List<FieldError> fieldErrors) {
-        Map<String, String> errMap = null;
+        if (CollectionUtils.isEmpty(fieldErrors)) {
-
+            return Collections.emptyMap();
-        if (!CollectionUtils.isEmpty(fieldErrors)) {
-            // 如果不为空
-            errMap = new HashMap<>(4);
-            for (FieldError fieldError : fieldErrors) {
-                errMap.put(fieldError.getField(), fieldError.getDefaultMessage());
-            }
         }
 
+        Map<String, String> errMap = new HashMap<>(4);
+        fieldErrors.forEach(filedError -> errMap.put(filedError.getField(), filedError.getDefaultMessage()));
         return errMap;
     }
-
-    public static String stringWithFieldError(List<FieldError> fieldErrors, boolean allError) {
-        StringBuilder errString = new StringBuilder();
-        if (!CollectionUtils.isEmpty(fieldErrors)) {
-            // 如果不为空
-            for (FieldError fieldError : fieldErrors) {
-                if (errString.length() > 0) {
-                    errString.append(",");
-                }
-                errString.append(fieldError.getField()).append(":").append(fieldError.getDefaultMessage());
-                if (!allError && errString.length() > 0) {
-                    return errString.toString();
-                }
-            }
-        }
-
-        return errString.toString();
-    }
 }

src/main/java/cc/ryanc/halo/web/controller/base/ControllerExceptionHandler.java

@@ -18,10 +18,8 @@ import org.springframework.web.bind.annotation.ResponseStatus;
 import org.springframework.web.bind.annotation.RestControllerAdvice;
 import org.springframework.web.servlet.NoHandlerFoundException;
 
-import javax.validation.ConstraintViolation;
 import javax.validation.ConstraintViolationException;
 import java.util.Map;
-import java.util.Set;
 
 /**
  * Exception handler of controller.
@@ -54,10 +52,10 @@ public class ControllerExceptionHandler {
     @ExceptionHandler(ConstraintViolationException.class)
     @ResponseStatus(HttpStatus.BAD_REQUEST)
     public BaseResponse handleConstraintViolationException(ConstraintViolationException e) {
-        BaseResponse<Set<ConstraintViolation<?>>> baseResponse = handleBaseException(e);
+        BaseResponse<Map<String, String>> baseResponse = handleBaseException(e);
         baseResponse.setStatus(HttpStatus.BAD_REQUEST.value());
         baseResponse.setMessage("Field validation error");
-        baseResponse.setData(e.getConstraintViolations());
+        baseResponse.setData(ValidationUtils.mapWithValidError(e.getConstraintViolations()));
         return baseResponse;
     }