Trail: Java Architecture for XML Binding (JAXB)
Lesson: Introduction to JAXB
Binding XML Schemas
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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:

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 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

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