Explicit support of String[] value resolution

This commit adds an explicit support for String array for value
resolution. <util:properties> switches the 'locations' property to a
String array in 662d8aa and this broke expression evaluation.

Issue: SPR-12391

Author: snicoll

spring-beans/src/main/java/org/springframework/beans/factory/support/BeanDefinitionValueResolver.java

@@ -200,6 +200,14 @@ else if (value instanceof TypedStringValue) {
 						"Error converting typed String value for " + argName, ex);
 			}
 		}
+		else if (value instanceof String[]) {
+			String[] values = (String[]) value;
+			Object[] resolvedValues = new Object[values.length];
+			for (int i = 0; i < values.length; i++) {
+				resolvedValues[i] = evaluate(values[i]);
+			}
+			return resolvedValues;
+		}
 		else {
 			return evaluate(value);
 		}

spring-beans/src/test/java/org/springframework/beans/factory/DefaultListableBeanFactoryTests.java

@@ -41,6 +41,7 @@
 import org.junit.Rule;
 import org.junit.Test;
 import org.junit.rules.ExpectedException;
+import org.mockito.Matchers;
 
 import org.springframework.beans.BeansException;
 import org.springframework.beans.MutablePropertyValues;
@@ -52,10 +53,13 @@
 import org.springframework.beans.TypeMismatchException;
 import org.springframework.beans.factory.config.AutowireCapableBeanFactory;
 import org.springframework.beans.factory.config.BeanDefinition;
+import org.springframework.beans.factory.config.BeanExpressionContext;
+import org.springframework.beans.factory.config.BeanExpressionResolver;
 import org.springframework.beans.factory.config.BeanPostProcessor;
 import org.springframework.beans.factory.config.ConfigurableBeanFactory;
 import org.springframework.beans.factory.config.ConstructorArgumentValues;
 import org.springframework.beans.factory.config.InstantiationAwareBeanPostProcessorAdapter;
+import org.springframework.beans.factory.config.PropertiesFactoryBean;
 import org.springframework.beans.factory.config.RuntimeBeanReference;
 import org.springframework.beans.factory.config.TypedStringValue;
 import org.springframework.beans.factory.support.AbstractBeanDefinition;
@@ -1165,6 +1169,23 @@ public void testDoubleArrayConstructorWithOptionalAutowiring() throws MalformedU
 		assertNull(ab.getResourceArray());
 	}
 
+	@Test
+	public void testExpressionInStringArray() {
+		DefaultListableBeanFactory bf = new DefaultListableBeanFactory();
+		BeanExpressionResolver beanExpressionResolver = mock(BeanExpressionResolver.class);
+		when(beanExpressionResolver.evaluate(eq("#{foo}"), Matchers.any(BeanExpressionContext.class)))
+				.thenReturn("classpath:/org/springframework/beans/factory/xml/util.properties");
+		bf.setBeanExpressionResolver(beanExpressionResolver);
+
+		RootBeanDefinition rbd = new RootBeanDefinition(PropertiesFactoryBean.class);
+		MutablePropertyValues pvs = new MutablePropertyValues();
+		pvs.add("locations", new String[]{"#{foo}"});
+		rbd.setPropertyValues(pvs);
+		bf.registerBeanDefinition("myProperties", rbd);
+		Properties properties = (Properties) bf.getBean("myProperties");
+		assertEquals("bar", properties.getProperty("foo"));
+	}
+
 	@Test
 	public void testAutowireWithNoDependencies() {
 		DefaultListableBeanFactory lbf = new DefaultListableBeanFactory();