Handle non-void write methods deterministically

This change resolves a specific issue with processing
java.math.BigDecimal via ExtendedBeanInfo. BigDecimal has a particular
constellation of #setScale methods that, prior to this change, had the
potential to cause ExtendedBeanInfo to throw an IntrospectionException
depending on the order in which the methods were processed.

Because JDK 7 no longer returns deterministic results from
Class#getDeclaredMethods, it became a genuine possibility - indeed a
statistical certainty that the 'wrong' setScale method handling order
happens sooner or later. Typically one could observe this failure once
out of every four test runs.

This commit introduces deterministic method ordering of all discovered
non-void returning write methods in such a way that solves the problem
for BigDecimal as well as for any other class having a similar method
arrangement.

Also:

 - Remove unnecessary cast

 - Pass no method information to PropertyDescriptor superclasses when
   invoking super(...). This ensures that any 'type mismatch'
   IntrospectionExceptions are handled locally in ExtendedBeanInfo and
   its Simple* PropertyDescriptor variants where we have full control.

Issue: SPR-10111, SPR-9702

Author: cbeams

org.springframework.beans/src/main/java/org/springframework/beans/ExtendedBeanInfo.java

@@ -31,6 +31,7 @@
 import java.lang.reflect.Modifier;
 
 import java.util.ArrayList;
+import java.util.Collections;
 import java.util.Comparator;
 import java.util.Enumeration;
 import java.util.List;
@@ -115,6 +116,14 @@ private List<Method> findNonVoidWriteMethods(MethodDescriptor[] methodDescriptor
 				matches.add(method);
 			}
 		}
+		// sort non-void returning write methods to guard against the ill effects of
+		// non-deterministic sorting of methods returned from Class#getDeclaredMethods
+		// under JDK 7. See http://bugs.sun.com/view_bug.do?bug_id=7023180
+		Collections.sort(matches, new Comparator<Method>() {
+			public int compare(Method m1, Method m2) {
+				return m2.toString().compareTo(m1.toString());
+			}
+		});
 		return matches;
 	}
 
@@ -260,7 +269,7 @@ public SimpleNonIndexedPropertyDescriptor(PropertyDescriptor original)
 	public SimpleNonIndexedPropertyDescriptor(String propertyName,
 			Method readMethod, Method writeMethod) throws IntrospectionException {
 
-		super(propertyName, readMethod, writeMethod);
+		super(propertyName, null, null);
 		this.setReadMethod(readMethod);
 		this.setWriteMethod(writeMethod);
 		this.propertyType = findPropertyType(readMethod, writeMethod);
@@ -349,7 +358,7 @@ public SimpleIndexedPropertyDescriptor(String propertyName,
 				Method indexedReadMethod, Method indexedWriteMethod)
 			throws IntrospectionException {
 
-		super(propertyName, readMethod, writeMethod, indexedReadMethod, indexedWriteMethod);
+		super(propertyName, null, null, null, null);
 		this.setReadMethod(readMethod);
 		this.setWriteMethod(writeMethod);
 		this.propertyType = findPropertyType(readMethod, writeMethod);
@@ -494,7 +503,7 @@ public static void copyNonMethodProperties(PropertyDescriptor source, PropertyDe
 		// copy all attributes (emulating behavior of private FeatureDescriptor#addTable)
 		Enumeration<String> keys = source.attributeNames();
 		while (keys.hasMoreElements()) {
-			String key = (String)keys.nextElement();
+			String key = keys.nextElement();
 			target.setValue(key, source.getValue(key));
 		}
 

org.springframework.beans/src/test/java/org/springframework/beans/ExtendedBeanInfoTests.java

@@ -23,6 +23,7 @@
 import java.beans.PropertyDescriptor;
 
 import java.lang.reflect.Method;
+import java.math.BigDecimal;
 
 import org.junit.Test;
 
@@ -582,6 +583,20 @@ class C {
 		}
 	}
 
+	/**
+	 * Prior to SPR-10111 (a follow-up fix for SPR-9702), this method would throw an
+	 * IntrospectionException regarding a "type mismatch between indexed and non-indexed
+	 * methods" intermittently (approximately one out of every four times) under JDK 7
+	 * due to non-deterministic results from {@link Class#getDeclaredMethods()}.
+	 * See http://bugs.sun.com/view_bug.do?bug_id=7023180
+	 * @see #cornerSpr9702()
+	 */
+	@Test
+	public void cornerSpr10111() throws Exception {
+		new ExtendedBeanInfo(Introspector.getBeanInfo(BigDecimal.class));
+	}
+
+
 	@Test
 	public void subclassWriteMethodWithCovariantReturnType() throws IntrospectionException {
 		@SuppressWarnings("unused") class B {
@@ -694,7 +709,7 @@ public void overloadedNonStandardWriteMethodsOnly_orderB() throws IntrospectionE
 
 		for (PropertyDescriptor pd : ebi.getPropertyDescriptors()) {
 			if (pd.getName().equals("foo")) {
-				assertThat(pd.getWriteMethod(), is(C.class.getMethod("setFoo", int.class)));
+				assertThat(pd.getWriteMethod(), is(C.class.getMethod("setFoo", String.class)));
 				return;
 			}
 		}
@@ -732,7 +747,7 @@ public void reproSpr8522() throws IntrospectionException {
 		assertThat(hasReadMethodForProperty(ebi, "dateFormat"), is(false));
 		assertThat(hasWriteMethodForProperty(ebi, "dateFormat"), is(true));
 		assertThat(hasIndexedReadMethodForProperty(ebi, "dateFormat"), is(false));
-		assertThat(hasIndexedWriteMethodForProperty(ebi, "dateFormat"), is(true));
+		assertThat(hasIndexedWriteMethodForProperty(ebi, "dateFormat"), is(trueUntilJdk17()));
 	}
 
 	@Test
@@ -943,4 +958,5 @@ public void setAddress(int index, String addr) { }
 			assertThat(hasIndexedWriteMethodForProperty(bi, "address"), is(true));
 		}
 	}
+
 }