Data Objects
Both PageHeader and PageBody are "wrappers" on underlying Maps that hold datatypes of various types, keyed by field names (Strings). The valid field names for a service are described in the service meta info file (an xml document). Null values are not allowed; use empty strings to represent missing values (e.g. for null date).
Note that most system datatypes are represented in these Java objects as simple Strings. Note the following:
Booleans are represented by the Java Boolean class
Date values are represented as Strings in the format YYYY-MM-DD
Date/Time values are represented as Strings in the format YYYY-MM-DD-HH:MM:SS
Time values are represented as Strings in the format HH:MM:SS
BigInteger values are represented as Java BigInteger values
BigDecimal and Money values are represented as Java BigDecimal values, with the appropriate scale.