fix:获取锁key时，当参数值为null时抛空指针的异常

Author: klboke

src/main/java/org/springframework/boot/autoconfigure/klock/core/BusinessKeyProvider.java

@@ -12,6 +12,7 @@
 import org.springframework.expression.ExpressionParser;
 import org.springframework.expression.spel.standard.SpelExpressionParser;
 import org.springframework.expression.spel.support.StandardEvaluationContext;
+import org.springframework.util.ObjectUtils;
 import org.springframework.util.StringUtils;
 
 import java.lang.reflect.Method;
@@ -56,10 +57,10 @@ private Method getMethod(JoinPoint joinPoint) {
     private List<String> getSpelDefinitionKey(String[] definitionKeys, Method method, Object[] parameterValues) {
         List<String> definitionKeyList = new ArrayList<>();
         for (String definitionKey : definitionKeys) {
-            if (definitionKey != null && !definitionKey.isEmpty()) {
+            if (!ObjectUtils.isEmpty(definitionKey)) {
                 EvaluationContext context = new MethodBasedEvaluationContext(null, method, parameterValues, nameDiscoverer);
-                String key = parser.parseExpression(definitionKey).getValue(context).toString();
-                definitionKeyList.add(key);
+                Object objKey = parser.parseExpression(definitionKey).getValue(context);
+                definitionKeyList.add(ObjectUtils.nullSafeToString(objKey));
             }
         }
         return definitionKeyList;
@@ -71,11 +72,12 @@ private List<String> getParameterKey(Parameter[] parameters, Object[] parameterV
             if (parameters[i].getAnnotation(KlockKey.class) != null) {
                 KlockKey keyAnnotation = parameters[i].getAnnotation(KlockKey.class);
                 if (keyAnnotation.value().isEmpty()) {
-                    parameterKey.add(parameterValues[i].toString());
+                    Object parameterValue = parameterValues[i];
+                    parameterKey.add(ObjectUtils.nullSafeToString(parameterValue));
                 } else {
                     StandardEvaluationContext context = new StandardEvaluationContext(parameterValues[i]);
-                    String key = parser.parseExpression(keyAnnotation.value()).getValue(context).toString();
-                    parameterKey.add(key);
+                    Object key = parser.parseExpression(keyAnnotation.value()).getValue(context);
+                    parameterKey.add(ObjectUtils.nullSafeToString(key));
                 }
             }
         }

src/test/java/org/springframework/boot/autoconfigure/klock/test/KlockTests.java

@@ -84,7 +84,7 @@ public void jvm3()throws Exception{
 	 */
 	@Test
 	public void businessKeyJvm1()throws Exception{
-		String result=testService.getValue("user1",1);
+		String result=testService.getValue("user1",null);
 		Assert.assertEquals(result,"success");
 	}
 	/**
@@ -108,7 +108,7 @@ public void businessKeyJvm3()throws Exception{
 	 */
 	@Test
 	public void businessKeyJvm4()throws Exception{
-		String result=testService.getValue(new User(3,"kl"));
+		String result=testService.getValue(new User(3,null));
 		Assert.assertEquals(result,"success");
 	}
 

src/test/java/org/springframework/boot/autoconfigure/klock/test/TestService.java

@@ -20,7 +20,7 @@ public String getValue(String param) throws Exception {
     }
 
     @Klock(keys = {"#userId"})
-    public String getValue(String userId,@KlockKey int id)throws Exception{
+    public String getValue(String userId,@KlockKey Integer id)throws Exception{
         Thread.sleep(60*1000);
         return "success";
     }