In "Jaspersoft Studio User Guide" page 104 "10.4 Understanding the JRDataSource Interface", the second paragraph is wrong.
"The first method, public boolean next(), is useful for moving a virtual cursor to the next record. In fact, data supplied by
a JRDataSource is ideally organized into records as in a table. The second method, public Object getFieldValue(JRField jrField)
, returns true if the cursor is positioned correctly in the subsequent record, false if there are no more available records"
The method names are interchanged. next() records returns boolean values "true" or "false" depending on whether there is a next record. getFieldValue() method is used to get the next record when it exists.
jaspersoft-studio-user-guide_1.pdf (version 6.0) contain this error