Supported XML and Java^TM types

An issue that sometimes creates confusion when using Web Services is the appropriate mapping of the XML types to Java types and vice versa. JSR-172 uses the mapping shown in the table below to assign XML and Java types.

Notice that the types xsd:float and xsd:double may be mapped to either the Java types float and double or to String. This is to account for the fact that the CLDC 1.0 platform doesn't support these types. In a CLDC 1.0 platform, these values would be converted to a String using a platform-dependent format, while in CLDC 1.1 the stub will use the floating-point types. Another consequence of this fact is that stubs generated for a CLDC 1.1 implementation may not work properly in CLDC 1.0.

Besides the types indicated in the table above, the basic types may be mapped not to the primitive Java types but to their wrappers instead. This is to take into account that these values may be marked as nullable or optional and this cannot be represented using the Java primitive types. In this case the mapping will be done as indicated in the table below.

Finally the JAX-RPC subset in JSR-172 contains support for arrays and complex structures enclosed in an xsd:completeType element.