Why is this Groovy code trying to cast? - groovy

Question

Im getting a cast exception thrown at the line "handDetailList.each". I don't understand why my code is trying to cast a list to a "Hand" class? It seems to me that sometimes Groovy does strange things with casting....?
private Hand buildHands(List handDetailList) {
def parsedHand = new Hand()
parsedHand.setTableName(handDetailList.get(1))
handDetailList.each {
}
}
I get the following exception (I have edited the exception, line 70 is "handDetailList.each {"):
Exception in thread "main" org.codehaus.groovy.runtime.typehandling.GroovyCastException: Cannot cast object <details of the list, omitted> with class 'java.util.ArrayList' to class 'gameMechanics.Hand' due to: groovy.lang.GroovyRuntimeException: Could not find matching constructor for: gameMechanics.Hand(java.lang.String,........
at org.codehaus.groovy.runtime.typehandling.DefaultTypeTransformation.castToType(DefaultTypeTransformation.java:358)
at org.codehaus.groovy.runtime.ScriptBytecodeAdapter.castToType(ScriptBytecodeAdapter.java:599)
at advisor.HistoryParser.buildHands(HistoryParser.groovy:70)
at advisor.HistoryParser.this$2$buildHands(HistoryParser.groovy)
at advisor.HistoryParser$this$2$buildHands.callCurrent(Unknown Source)
at org.codehaus.groovy.runtime.callsite.CallSiteArray.defaultCallCurrent(CallSiteArray.java:49)
at org.codehaus.groovy.runtime.callsite.AbstractCallSite.callCurrent(AbstractCallSite.java:133)
at org.codehaus.groovy.runtime.callsite.AbstractCallSite.callCurrent(AbstractCallSite.java:141)
at advisor.HistoryParser.parse(HistoryParser.groovy:57)
at advisor.HistoryParser$parse.call(Unknown Source)

Answer 1

each returns the list that each was called on.
You have said the function returns an object of type Hand, and as Groovy automatically returns the last statement in a method, it is trying to convert the list to an instance of Hand and failing...
What is it you want to return? The parsedHand variable?
Maybe try:
private Hand buildHands(List handDetailList) {
def parsedHand = new Hand()
parsedHand.setTableName(handDetailList.get(1))
handDetailList.each {
}
parsedHand
}
if so.