From bc3e560ad33966c4abe25925ea1f6d03a234623c Mon Sep 17 00:00:00 2001
From: bbaia <brbaia@gmail.com>
Date: Wed, 22 Sep 2010 09:26:05 +0000
Subject: [PATCH] Add 'when' condition to the Reference Validator (SPRNET-1370)

---
 .../Config/ValidationNamespaceParser.cs       |  5 ++
 .../Config/spring-validation-1.3.xsd          |  5 ++
 .../Validation/ValidatorReference.cs          | 57 ++++++++++++++++---
 .../Validation/ValidatorReferenceTests.cs     | 25 +++++++-
 4 files changed, 81 insertions(+), 11 deletions(-)

diff --git a/src/Spring/Spring.Core/Validation/Config/ValidationNamespaceParser.cs b/src/Spring/Spring.Core/Validation/Config/ValidationNamespaceParser.cs
index dc2984dc..bc0ca37b 100644
--- a/src/Spring/Spring.Core/Validation/Config/ValidationNamespaceParser.cs
+++ b/src/Spring/Spring.Core/Validation/Config/ValidationNamespaceParser.cs
@@ -341,6 +341,7 @@ namespace Spring.Validation.Config
             string typeName = "Spring.Validation.ValidatorReference, Spring.Core";
             string name = GetAttributeValue(element, ValidatorDefinitionConstants.ReferenceNameAttribute);
             string context = GetAttributeValue(element, ValidatorDefinitionConstants.ReferenceContextAttribute);
+            string when = GetAttributeValue(element, ValidatorDefinitionConstants.WhenAttribute);
 
             MutablePropertyValues properties = new MutablePropertyValues();
             properties.Add("Name", name);
@@ -348,6 +349,10 @@ namespace Spring.Validation.Config
             {
                 properties.Add("Context", context);
             }
+            if (StringUtils.HasText(when))
+            {
+                properties.Add("When", when);
+            }
 
             IConfigurableObjectDefinition reference =
                 parserContext.ReaderContext.ObjectDefinitionFactory.CreateObjectDefinition(typeName, null, parserContext.ReaderContext.Reader.Domain);
diff --git a/src/Spring/Spring.Core/Validation/Config/spring-validation-1.3.xsd b/src/Spring/Spring.Core/Validation/Config/spring-validation-1.3.xsd
index e646969b..82dec005 100644
--- a/src/Spring/Spring.Core/Validation/Config/spring-validation-1.3.xsd
+++ b/src/Spring/Spring.Core/Validation/Config/spring-validation-1.3.xsd
@@ -107,6 +107,11 @@
                 <xs:documentation><![CDATA[A SpEL expression evaluating to the context to switch to when evaluating the referenced validator.]]></xs:documentation>
             </xs:annotation>
         </xs:attribute>
+        <xs:attribute name="when" type="objects:nonNullString" use="optional">
+          <xs:annotation>
+            <xs:documentation><![CDATA[A boolean SpEL expression that determines if this validator shall be executed.]]></xs:documentation>
+          </xs:annotation>
+        </xs:attribute>
     </xs:complexType>
 
     <xs:complexType name="baseValidatorType">
diff --git a/src/Spring/Spring.Core/Validation/ValidatorReference.cs b/src/Spring/Spring.Core/Validation/ValidatorReference.cs
index b32d6f80..2924066e 100644
--- a/src/Spring/Spring.Core/Validation/ValidatorReference.cs
+++ b/src/Spring/Spring.Core/Validation/ValidatorReference.cs
@@ -22,6 +22,7 @@ using System.Collections;
 
 using Spring.Expressions;
 using Spring.Objects.Factory;
+using System;
 
 namespace Spring.Validation
 {
@@ -47,6 +48,7 @@ namespace Spring.Validation
 
         private string name;
         private IExpression context;
+        private IExpression when;
         private IValidator validator;
 
         #endregion
@@ -54,11 +56,32 @@ namespace Spring.Validation
         #region Constructors
 
         /// <summary>
-        /// Initializes a new instance of the <see cref="ValidatorReference"/> class.
+        /// Creates a new instance of the <see cref="ValidatorReference"/> class.
         /// </summary>
         public ValidatorReference()
         {}
 
+        /// <summary>
+        /// Creates a new instance of the <see cref="ValidatorReference"/> class.
+        /// </summary>
+        /// <param name="when">
+        /// The expression that determines if this validator should be evaluated.
+        /// </param>
+        public ValidatorReference(string when)
+            : this((when != null ? Expression.Parse(when) : null))
+        {}
+
+        /// <summary>
+        /// Creates a new instance of the <see cref="ValidatorReference"/> class.
+        /// </summary>
+        /// <param name="when">
+        /// The expression that determines if this validator should be evaluated.
+        /// </param>
+        public ValidatorReference(IExpression when)
+        {
+            this.when = when;
+        }
+
         #endregion
 
         #region Properties
@@ -83,6 +106,16 @@ namespace Spring.Validation
             set { context = value; }
         }
 
+        /// <summary>
+        /// Gets or sets the expression that determines if this validator should be evaluated.
+        /// </summary>
+        /// <value>The expression that determines if this validator should be evaluated.</value>
+        public IExpression When
+        {
+            get { return when; }
+            set { when = value; }
+        }
+
         #endregion
 
         /// <summary>
@@ -105,17 +138,23 @@ namespace Spring.Validation
         /// <returns><c>True</c> if validation was successful, <c>False</c> otherwise.</returns>
         public bool Validate(object validationContext, IDictionary contextParams, IValidationErrors errors)
         {
-            if (Context != null)
+            bool valid = true;
+
+            if (When == null || 
+                Convert.ToBoolean(When.GetValue(validationContext, contextParams)))
             {
-                validationContext = Context.GetValue(validationContext, contextParams);
+                if (Context != null)
+                {
+                    validationContext = Context.GetValue(validationContext, contextParams);
+                }
+                if (validator == null)
+                {
+                    validator = (IValidator)objectFactory.GetObject(Name);
+                }
+                valid = validator.Validate(validationContext, contextParams, errors);
             }
 
-            if (validator == null)
-            {
-                validator = (IValidator) objectFactory.GetObject(Name);
-            }
-
-            return validator.Validate(validationContext, contextParams, errors);
+            return valid;
         }
 
         /// <summary>
diff --git a/test/Spring/Spring.Core.Tests/Validation/ValidatorReferenceTests.cs b/test/Spring/Spring.Core.Tests/Validation/ValidatorReferenceTests.cs
index 8e29f440..dc1c8b97 100644
--- a/test/Spring/Spring.Core.Tests/Validation/ValidatorReferenceTests.cs
+++ b/test/Spring/Spring.Core.Tests/Validation/ValidatorReferenceTests.cs
@@ -40,7 +40,7 @@ namespace Spring.Validation
             StaticListableObjectFactory factory = new StaticListableObjectFactory();
             factory.AddObject("validator", new TrueValidator());
 
-            ValidatorReference v = new ValidatorReference();
+            ValidatorReference v = new ValidatorReference("true");
             v.ObjectFactory = factory;
             v.Name = "validator";
 
@@ -65,6 +65,21 @@ namespace Spring.Validation
             Assert.IsFalse(v.Validate(null, errors));
         }
 
+        [Test]
+        public void FalseValidatorReferenceNotEvaluatedBecauseWhenExpressionReturnsFalse()
+        {
+            StaticListableObjectFactory factory = new StaticListableObjectFactory();
+            factory.AddObject("validator", new FalseValidator());
+
+            ValidatorReference v = new ValidatorReference("false");
+            v.ObjectFactory = factory;
+            v.Name = "validator";
+
+            IValidationErrors errors = new ValidationErrors();
+            Assert.IsTrue(v.Validate(null, null, errors));
+            Assert.IsTrue(v.Validate(null, errors));
+        }
+
         [Test]
         public void ContextNarrowing()
         {
@@ -93,7 +108,13 @@ namespace Spring.Validation
 
             Assert.IsTrue(v2.Validate(context, null, errors));
             Assert.IsTrue(v2.Validate(context, errors));
-        }
 
+            ValidatorReference v3 = new ValidatorReference("false");
+            v3.ObjectFactory = factory;
+            v3.Name = "cv2";
+            v3.Context = Expression.Parse("DOB");
+
+            Assert.IsTrue(v3.Validate(null, errors));
+        }
     }
 }
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