Java tutorial
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However, if you add GPL Version 2 code * and therefore, elected the GPL Version 2 license, then the option applies * only if the new code is made subject to such option by the copyright * holder. */ package javax.xml.bind.annotation; import javax.xml.bind.annotation.adapters.XmlJavaTypeAdapter; import java.lang.annotation.Retention; import java.lang.annotation.Target; import static java.lang.annotation.ElementType.*; import static java.lang.annotation.ElementType.PARAMETER; import static java.lang.annotation.RetentionPolicy.*; /** * Maps a JavaBean property to a XML element derived from property name. * * <p> <b>Usage</b> * <p> * {@code @XmlElement} annotation can be used with the following program * elements: * <ul> * <li> a JavaBean property </li> * <li> non static, non transient field </li> * <li> within {@link XmlElements} * </ul> * * The usage is subject to the following constraints: * <ul> * <li> This annotation can be used with following annotations: * {@link XmlID}, * {@link XmlIDREF}, * {@link XmlList}, * {@link XmlSchemaType}, * {@link XmlValue}, * {@link XmlAttachmentRef}, * {@link XmlMimeType}, * {@link XmlInlineBinaryData}, * {@link XmlElementWrapper}, * {@link XmlJavaTypeAdapter}</li> * <li> if the type of JavaBean property is a collection type of * array, an indexed property, or a parameterized list, and * this annotation is used with {@link XmlElements} then, * {@code @XmlElement.type()} must be DEFAULT.class since the * collection item type is already known. </li> * </ul> * * <p> * A JavaBean property, when annotated with @XmlElement annotation * is mapped to a local element in the XML Schema complex type to * which the containing class is mapped. * * <p> * <b>Example 1: </b> Map a public non static non final field to local * element * <pre> * //Example: Code fragment * public class USPrice { * {@literal @}XmlElement(name="itemprice") * public java.math.BigDecimal price; * } * {@code * * <!-- Example: Local XML Schema element --> * <xs:complexType name="USPrice"/> * <xs:sequence> * <xs:element name="itemprice" type="xs:decimal" minOccurs="0"/> * </sequence> * </xs:complexType> * }</pre> * <p> * * <b> Example 2: </b> Map a field to a nillable element. * <pre> * //Example: Code fragment * public class USPrice { * {@literal @}XmlElement(nillable=true) * public java.math.BigDecimal price; * } * {@code * * <!-- Example: Local XML Schema element --> * <xs:complexType name="USPrice"> * <xs:sequence> * <xs:element name="price" type="xs:decimal" nillable="true" minOccurs="0"/> * </sequence> * </xs:complexType> * }</pre> * <p> * <b> Example 3: </b> Map a field to a nillable, required element. * <pre> * //Example: Code fragment * public class USPrice { * {@literal @}XmlElement(nillable=true, required=true) * public java.math.BigDecimal price; * } * {@code * * <!-- Example: Local XML Schema element --> * <xs:complexType name="USPrice"> * <xs:sequence> * <xs:element name="price" type="xs:decimal" nillable="true" minOccurs="1"/> * </sequence> * </xs:complexType> * }</pre> * * <p> <b>Example 4: </b>Map a JavaBean property to an XML element * with anonymous type.</p> * <p> * See Example 6 in @{@link XmlType}. * * @author Sekhar Vajjhala, Sun Microsystems, Inc. * @since 1.6, JAXB 2.0 */ @Retention(RUNTIME) @Target({ FIELD, METHOD, PARAMETER }) public @interface XmlElement { /** * Name of the XML Schema element. * <p> If the value is "##default", then element name is derived from the * JavaBean property name. */ String name() default "##default"; /** * Customize the element declaration to be nillable. * <p>If nillable() is true, then the JavaBean property is * mapped to a XML Schema nillable element declaration. */ boolean nillable() default false; /** * Customize the element declaration to be required. * <p>If required() is true, then Javabean property is mapped to * an XML schema element declaration with minOccurs="1". * maxOccurs is "1" for a single valued property and "unbounded" * for a multivalued property. * <p>If required() is false, then the Javabean property is mapped * to XML Schema element declaration with minOccurs="0". * maxOccurs is "1" for a single valued property and "unbounded" * for a multivalued property. */ boolean required() default false; /** * XML target namespace of the XML Schema element. * <p> * If the value is "##default", then the namespace is determined * as follows: * <ol> * <li> * If the enclosing package has {@link XmlSchema} annotation, * and its {@link XmlSchema#elementFormDefault() elementFormDefault} * is {@link XmlNsForm#QUALIFIED QUALIFIED}, then the namespace of * the enclosing class. * * <li> * Otherwise {@literal ''} (which produces unqualified element in the default * namespace. * </ol> */ String namespace() default "##default"; /** * Default value of this element. * * <p> * The <pre>'\u0000'</pre> value specified as a default of this annotation element * is used as a poor-man's substitute for null to allow implementations * to recognize the 'no default value' state. */ String defaultValue() default "\u0000"; /** * The Java class being referenced. */ Class type() default DEFAULT.class; /** * Used in {@link XmlElement#type()} to * signal that the type be inferred from the signature * of the property. */ static final class DEFAULT { } }