1 files changed, 33 insertions, 7 deletions

diff --git a/spring-context/src/main/java/org/springframework/context/expression/CachedExpressionEvaluator.java b/spring-context/src/main/java/org/springframework/context/expression/CachedExpressionEvaluator.java
index 4bb20b28..d530db80 100644
--- a/spring-context/src/main/java/org/springframework/context/expression/CachedExpressionEvaluator.java
+++ b/spring-context/src/main/java/org/springframework/context/expression/CachedExpressionEvaluator.java
@@ -18,6 +18,8 @@ package org.springframework.context.expression;
 
 import java.util.Map;
 
+import org.springframework.core.DefaultParameterNameDiscoverer;
+import org.springframework.core.ParameterNameDiscoverer;
 import org.springframework.expression.Expression;
 import org.springframework.expression.spel.standard.SpelExpressionParser;
 import org.springframework.util.Assert;
@@ -35,12 +37,14 @@ public abstract class CachedExpressionEvaluator {
 
 	private final SpelExpressionParser parser;
 
+	private final ParameterNameDiscoverer parameterNameDiscoverer = new DefaultParameterNameDiscoverer();
+
 
 	/**
 	 * Create a new instance with the specified {@link SpelExpressionParser}.
 	 */
 	protected CachedExpressionEvaluator(SpelExpressionParser parser) {
-		Assert.notNull(parser, "Parser must not be null");
+		Assert.notNull(parser, "SpelExpressionParser must not be null");
 		this.parser = parser;
 	}
 
@@ -59,6 +63,14 @@ public abstract class CachedExpressionEvaluator {
 		return this.parser;
 	}
 
+	/**
+	 * Return a shared parameter name discoverer which caches data internally.
+	 * @since 4.3
+	 */
+	protected ParameterNameDiscoverer getParameterNameDiscoverer() {
+		return this.parameterNameDiscoverer;
+	}
+
 
 	/**
 	 * Return the {@link Expression} for the specified SpEL value
@@ -84,14 +96,14 @@ public abstract class CachedExpressionEvaluator {
 	}
 
 
-	protected static class ExpressionKey {
+	protected static class ExpressionKey implements Comparable<ExpressionKey> {
 
-		private final AnnotatedElementKey key;
+		private final AnnotatedElementKey element;
 
 		private final String expression;
 
-		protected ExpressionKey(AnnotatedElementKey key, String expression) {
-			this.key = key;
+		protected ExpressionKey(AnnotatedElementKey element, String expression) {
+			this.element = element;
 			this.expression = expression;
 		}
 
@@ -104,13 +116,27 @@ public abstract class CachedExpressionEvaluator {
 				return false;
 			}
 			ExpressionKey otherKey = (ExpressionKey) other;
-			return (this.key.equals(otherKey.key) &&
+			return (this.element.equals(otherKey.element) &&
 					ObjectUtils.nullSafeEquals(this.expression, otherKey.expression));
 		}
 
 		@Override
 		public int hashCode() {
-			return this.key.hashCode() + (this.expression != null ? this.expression.hashCode() * 29 : 0);
+			return this.element.hashCode() + (this.expression != null ? this.expression.hashCode() * 29 : 0);
+		}
+
+		@Override
+		public String toString() {
+			return this.element + (this.expression != null ? " with expression \"" + this.expression : "\"");
+		}
+
+		@Override
+		public int compareTo(ExpressionKey other) {
+			int result = this.element.toString().compareTo(other.element.toString());
+			if (result == 0 && this.expression != null) {
+				result = this.expression.compareTo(other.expression);
+			}
+			return result;
 		}
 	}