Steps to Reproduce

run attached unit test TreeRenderByPathTest.java

Current Result

exception when the path is just 1 greater than the children size

java.lang.IndexOutOfBoundsException: Index: 3

	at java.base/java.util.AbstractSequentialList.get(AbstractSequentialList.java:90)
	at org.zkoss.zul.Tree.renderItemByPath(Tree.java:2562)
	at TreeRenderByPathTest.test(TreeRenderByPathTest.java:45)

Expected Result

no exception, if the path is incorrect
return null as in the negative index case or any other case of incorrect path

Debug Information

https://github.com/zkoss/zk/blob/v9.5.0.2/zul/src/org/zkoss/zul/Tree.java#L2558
condition should be using >=

Workaround