refactor(apollo-client): Optimize the exception message when failing to retrieve configuration information.

CHANGES.md

@@ -5,6 +5,6 @@ Release Notes.
 Apollo Java 2.2.0
 
 ------------------
-
+[refactor(apollo-client): Optimize the exception message when failing to retrieve configuration information.](https://github.com/apolloconfig/apollo-java/pull/22)
 ------------------
 All issues and pull requests are [here](https://github.com/apolloconfig/apollo-java/milestone/2?closed=1)

apollo-client/src/main/java/com/ctrip/framework/apollo/util/ExceptionUtil.java

@@ -52,11 +52,19 @@ public static String getDetailMessage(Throwable ex) {
         counter--;
         continue;
       }
-      builder.append(" [Cause: ").append(cause.getMessage());
+      builder.append(" [Cause: ")
+              .append(getThrowingClassName(cause))
+              .append("(")
+              .append(cause.getMessage())
+              .append(")");
     }
 
     builder.append(Strings.repeat("]", counter));
 
     return builder.toString();
   }
+
+  public static String getThrowingClassName(Throwable throwable) {
+    return throwable.getClass().getSimpleName();
+  }
 }

apollo-client/src/test/java/com/ctrip/framework/apollo/util/ExceptionUtilTest.java

@@ -38,11 +38,11 @@ public void testGetDetailMessageWithCauses() throws Exception {
     String causeMsg2 = "another cause";
     String someMessage = "some message";
 
-    Throwable cause2 = new Throwable(causeMsg2);
+    Throwable cause2 = new Exception(causeMsg2);
     Throwable cause1 = new Throwable(causeMsg1, cause2);
     Throwable ex = new Throwable(someMessage, cause1);
 
-    String expected = someMessage + " [Cause: " + causeMsg1 + " [Cause: " + causeMsg2 + "]]";
+    String expected = someMessage + " [Cause: Throwable("+ causeMsg1 +") [Cause: Exception(" + causeMsg2 + ")]]";
     assertEquals(expected, ExceptionUtil.getDetailMessage(ex));
   }