StringIndexOutOfBoundsException issue

[jiangdequan]

Hi, wguttmn!
This error occurred at (JClassRegistry.java:467) when substring based on the logs below

Caused by: java.lang.StringIndexOutOfBoundsException: String index out of range: -1
	at java.lang.String.substring(String.java:1911)
	at org.exolab.castor.builder.JClassRegistry.ofTheSameType(JClassRegistry.java:467)
	at org.exolab.castor.builder.JClassRegistry.printStatistics(JClassRegistry.java:424)
	at org.exolab.castor.builder.SourceGenerator.generateSource(SourceGenerator.java:753)
	at org.exolab.castor.builder.SourceGenerator.generateSource(SourceGenerator.java:690)
	at org.exolab.castor.builder.SourceGenerator.generateSource(SourceGenerator.java:587)
	at org.codehaus.mojo.castor.GenerateMojo.processFile(GenerateMojo.java:530)

Here is the source code

private boolean ofTheSameType(final List<String> collisions) {
    boolean allSame = true;
    Iterator<String> iterator = collisions.iterator();
    String typeString = null;
    while (iterator.hasNext()) {
      String xPath = iterator.next();
      String newTypeString = xPath.substring(xPath.indexOf("[") + 1, xPath.indexOf("]"));// error occurred here
      if (typeString != null) {
        if (!typeString.equals(newTypeString)) {
          allSame = false;
          break;
        }
      } else {
        typeString = newTypeString;
      }
    }
    return allSame;
  }

I do not know much about the castor.But, the xPath`s value may have many diffrent types, such as
1.normal
a[bcdefg]h
2.only have [
a[bcdefgh
3.only have ]
abcde]fgh
4.none
abcdefgh
5.strange
ab]cde[fgh

From these types, type 1 and 4 offen appear in xPath.But the method ofTheSameType does not handle type 4.

The above is my analysis, please refer to.