Here is a quick reference for how input and output types map from xaction xml files to an Action bean:

xaction (XML) Action input	Java type	bean method (Java)
<myInput type="string">	java.lang.String	setMyInput(String s) { ...
<myInput type="long">	java.lang.Long	setMyInput(Long n) { ...
<myInputMap type="property-map">	java.util.Map<java.lang.String, java.lang.String>	setMyInputMap(Map<String, String> m) { ...
<myInputListMap type="property-map-list">	java.util.List<java.util.Map<java.lang.String, java.lang.String>>	setMyInputListMap(List<Map<String, String>> lm) { ...
<myInputList type="string-list">	java.util.List<java.lang.String>	setMyInputList(List<String> l) { ...
<myInput>	in this case, the Action framework does not know the type and will try to convert the data to the type specified in your Action's setter method. If the conversion fails, you will see a warning to this effect.	setMyInput(Object o), or setMyInput(SomeOtherType t) //of course this will only work if the data can be cast to a SomeOtherType type

xaction output	Java type	example (Java)
<myOutput type="content"/>	java.io.OutputStream	setMyOutputStream(OutputStream o) { ...

Resources

Action Error Handling

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