--- old/src/java.base/share/classes/java/lang/Class.java 2016-07-18 10:25:04.879368865 -0700 +++ new/src/java.base/share/classes/java/lang/Class.java 2016-07-18 10:25:04.755368860 -0700 @@ -238,15 +238,11 @@ TypeVariable[] typeparms = component.getTypeParameters(); if (typeparms.length > 0) { - boolean first = true; - sb.append('<'); + StringJoiner sj = new StringJoiner(",", "<", ">"); for(TypeVariable typeparm: typeparms) { - if (!first) - sb.append(','); - sb.append(typeparm.getTypeName()); - first = false; + sj.add(typeparm.getTypeName()); } - sb.append('>'); + sb.append(sj.toString()); } for (int i = 0; i < arrayDepth; i++)