UrlEncoded.decodeString throw StringIndexOutOfBoundsException

When invalid data was input to org.mortbay.util.UrlEncoded#decodeString , throw StringIndexOutOfBoundsException

url_encoded.decode("Name15=xx%zz", "UTF-8"); // <- throw StringIndexOutOfBoundsException

java.lang.StringIndexOutOfBoundsException: String index out of range: 12
at java.lang.String.charAt(Unknown Source)
at org.mortbay.util.UrlEncoded.decodeString(UrlEncoded.java:657)
at org.mortbay.util.UrlEncoded.decodeTo(UrlEncoded.java:227)
at org.mortbay.util.UrlEncoded.decode(UrlEncoded.java:82)
at org.mortbay.util.URLEncodedTest.testUrlEncoded(URLEncodedTest.java:150)

There was a problem in the processing of the invalid data.

$ svn diff
Index: UrlEncoded.java
===================================================================
— UrlEncoded.java (revision 6311)
+++ UrlEncoded.java (working copy)
@@ -653,7 +653,7 @@
catch(NumberFormatException nfe)

{ buffer.getStringBuffer().append('%'); - for(char next; ((next=encoded.charAt(++i+offset))!='%');) + for(char next; ( ((++i)+offset < encoded.length()) && (next=encoded.charAt(i+offset))!='%');) buffer.getStringBuffer().append((next=='+' ? ' ' : next)); }