1 files changed, 8 insertions, 13 deletions

diff --git a/luni/src/main/java/java/text/DateFormat.java b/luni/src/main/java/java/text/DateFormat.java
index b45e699..5ad4bb5 100644
--- a/luni/src/main/java/java/text/DateFormat.java
+++ b/luni/src/main/java/java/text/DateFormat.java
@@ -349,16 +349,14 @@ public abstract class DateFormat extends Format {
      *            {@code Number} instance.
      */
     @Override
-    public final StringBuffer format(Object object, StringBuffer buffer,
-            FieldPosition field) {
+    public final StringBuffer format(Object object, StringBuffer buffer, FieldPosition field) {
         if (object instanceof Date) {
             return format((Date) object, buffer, field);
         }
         if (object instanceof Number) {
-            return format(new Date(((Number) object).longValue()), buffer,
-                    field);
+            return format(new Date(((Number) object).longValue()), buffer, field);
         }
-        throw new IllegalArgumentException();
+        throw new IllegalArgumentException("Bad class: " + object.getClass());
     }
 
     /**
@@ -369,8 +367,7 @@ public abstract class DateFormat extends Format {
      * @return the formatted string.
      */
     public final String format(Date date) {
-        return format(date, new StringBuffer(), new FieldPosition(0))
-                .toString();
+        return format(date, new StringBuffer(), new FieldPosition(0)).toString();
     }
 
     /**
@@ -391,8 +388,7 @@ public abstract class DateFormat extends Format {
      *            of the alignment field in the formatted text.
      * @return the string buffer.
      */
-    public abstract StringBuffer format(Date date, StringBuffer buffer,
-            FieldPosition field);
+    public abstract StringBuffer format(Date date, StringBuffer buffer, FieldPosition field);
 
     /**
      * Returns an array of locales for which custom {@code DateFormat} instances
@@ -874,9 +870,8 @@ public abstract class DateFormat extends Format {
          */
         public static Field ofCalendarField(int calendarField) {
             if (calendarField < 0 || calendarField >= Calendar.FIELD_COUNT) {
-                throw new IllegalArgumentException();
+                throw new IllegalArgumentException("Field out of range: " + calendarField);
             }
-
             return table.get(Integer.valueOf(calendarField));
         }
     }
@@ -884,14 +879,14 @@ public abstract class DateFormat extends Format {
     private static void checkDateStyle(int style) {
         if (!(style == SHORT || style == MEDIUM || style == LONG
                 || style == FULL || style == DEFAULT)) {
-            throw new IllegalArgumentException("Illegal date style " + style);
+            throw new IllegalArgumentException("Illegal date style: " + style);
         }
     }
 
     private static void checkTimeStyle(int style) {
         if (!(style == SHORT || style == MEDIUM || style == LONG
                 || style == FULL || style == DEFAULT)) {
-            throw new IllegalArgumentException("Illegal time style " + style);
+            throw new IllegalArgumentException("Illegal time style: " + style);
         }
     }
 }