Binding XML Schemas
This section describes the default XML-to-Java bindings used by JAXB. All of these bindings can be overridden globally or case-by-case by using a custom binding declaration. See the JAXB Specification for complete information about the default JAXB bindings.
Simple Type Definitions
A schema component using a simple type definition typically binds to a Java property. Because there are different kinds of schema components, the following Java property attributes (common to the schema components) include:
- Base type
- Collection type, if any
- Predicate
The rest of the Java property attributes are specified in the schema component using the simple type definition.
Default Data Type Bindings
The following sections explain the default schema-to-Java, JAXBElement, and Java-to-schema data type bindings.
Schema-to-Java Mapping
The Java language provides a richer set of data types than the XML schema. The following table provides a mapping of XML data types to Java data types in JAXB.
Table: JAXB Mapping of XML Schema Built-in Data Types
| XML Schema Type | Java Data Type |
|---|---|
| xsd:string | java.lang.String |
| xsd:integer | java.math.BigInteger |
| xsd:int | int |
| xsd.long | long |
| xsd:short | short |
| xsd:decimal | java.math.BigDecimal |
| xsd:float | float |
| xsd:double | double |
| xsd:boolean | boolean |
| xsd:byte | byte |
| xsd:QName | javax.xml.namespace.QName |
| xsd:dateTime | javax.xml.datatype.XMLGregorianCalendar |
| xsd:base64Binary | byte[] |
| xsd:hexBinary | byte[] |
| xsd:unsignedInt | long |
| xsd:unsignedShort | int |
| xsd:unsignedByte | short |
| xsd:time | javax.xml.datatype.XMLGregorianCalendar |
| xsd:date | javax.xml.datatype.XMLGregorianCalendar |
| xsd:g | javax.xml.datatype.XMLGregorianCalendar |
| xsd:anySimpleType | java.lang.Object |
| xsd:anySimpleType | java.lang.String |
| xsd:duration | javax.xml.datatype.Duration |
| xsd:NOTATION | javax.xml.namespace.QName |
JAXBElement Object
When XML element information cannot be inferred by the derived Java representation of the XML content, a JAXBElement object is provided. This object has methods to get and set the object name and object value.
Java-to-Schema Mapping
The following table shows the default mapping of Java classes to XML data types.
Table: JAXB Mapping of XML Data Types to Java Classes
| Java Class | XML Data Type |
|---|---|
| java.lang.String | xs:string |
| java.math.BigInteger | xs:integer |
| java.math.BigDecimal | xs:decimal |
| java.util.Calendar | xs:dateTime |
| java.util.Date | xs:dateTime |
| javax.xml.namespace.QName | xs:QName |
| java.net.URI | xs:string |
| javax.xml.datatype.XMLGregorianCalendar | xs:anySimpleType |
| javax.xml.datatype.Duration | xs:duration |
| java.lang.Object | xs:anyType |
| java.awt.Image | xs:base64Binary |
| javax.activation.DataHandler | xs:base64Binary |
| javax.xml.transform.Source | xs:base64Binary |
| java.util.UUID | xs:string |