Class JAXB

java.lang.Object
jakarta.xml.bind.JAXB

public final class JAXB extends Object
Class that defines convenience methods for common, simple use of Jakarta XML Binding.

Methods defined in this class are convenience methods that combine several basic operations in the JAXBContext, Unmarshaller, and Marshaller. They are designed to be the preferred methods for developers new to Jakarta XML Binding. They have the following characteristics:

  1. Generally speaking, the performance is not necessarily optimal. It is expected that people who need to write performance critical code will use the rest of the Jakarta XML Binding API directly.
  2. Errors that happen during the processing is wrapped into DataBindingException (which will have JAXBException as its cause. It is expected that people who prefer the checked exception would use the rest of the Jakarta XML Binding API directly.

In addition, the unmarshal methods have the following characteristic:

  1. Schema validation is not performed on the input XML. The processing will try to continue even if there are errors in the XML, as much as possible. Only as the last resort, this method fails with DataBindingException.

Similarly, the marshal methods have the following characteristic:

  1. The processing will try to continue even if the Java object tree does not meet the validity requirement. Only as the last resort, this method fails with DataBindingException.

All the methods on this class require non-null arguments to all parameters. The unmarshal methods either fail with an exception or return a non-null value.

Since:
1.6, JAXB 2.1
  • Nested Class Summary

    Nested Classes
    Modifier and Type
    Class
    Description
    private static final class 
    To improve the performance, we'll cache the last JAXBContext used.
  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    private static WeakReference<JAXB.Cache>
    Cache.
  • Constructor Summary

    Constructors
    Modifier
    Constructor
    Description
    private
    No instantiation is allowed.
  • Method Summary

    Modifier and Type
    Method
    Description
    private static void
    _marshal(Object jaxbObject, Object xml)
    Writes a Java object tree to XML and store it to the specified location.
    private static <T> JAXBContext
    getContext(Class<T> type)
    Obtains the JAXBContext from the given type, by using the cache if possible.
    private static String
    inferName(Class<?> clazz)
     
    static void
    marshal(Object jaxbObject, File xml)
    Writes a Java object tree to XML and store it to the specified location.
    static void
    marshal(Object jaxbObject, OutputStream xml)
    Writes a Java object tree to XML and store it to the specified location.
    static void
    marshal(Object jaxbObject, Writer xml)
    Writes a Java object tree to XML and store it to the specified location.
    static void
    marshal(Object jaxbObject, String xml)
    Writes a Java object tree to XML and store it to the specified location.
    static void
    marshal(Object jaxbObject, URI xml)
    Writes a Java object tree to XML and store it to the specified location.
    static void
    marshal(Object jaxbObject, URL xml)
    Writes a Java object tree to XML and store it to the specified location.
    static void
    marshal(Object jaxbObject, Result xml)
    Writes a Java object tree to XML and store it to the specified location.
    private static Result
    Creates Result from various XML representation.
    private static Source
    Creates Source from various XML representation.
    static <T> T
    unmarshal(File xml, Class<T> type)
    Reads in a Java object tree from the given XML input.
    static <T> T
    unmarshal(InputStream xml, Class<T> type)
    Reads in a Java object tree from the given XML input.
    static <T> T
    unmarshal(Reader xml, Class<T> type)
    Reads in a Java object tree from the given XML input.
    static <T> T
    unmarshal(String xml, Class<T> type)
    Reads in a Java object tree from the given XML input.
    static <T> T
    unmarshal(URI xml, Class<T> type)
    Reads in a Java object tree from the given XML input.
    static <T> T
    unmarshal(URL xml, Class<T> type)
    Reads in a Java object tree from the given XML input.
    static <T> T
    unmarshal(Source xml, Class<T> type)
    Reads in a Java object tree from the given XML input.

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
  • Field Details

  • Constructor Details

    • JAXB

      private JAXB()
      No instantiation is allowed.
  • Method Details

    • getContext

      private static <T> JAXBContext getContext(Class<T> type) throws JAXBException
      Obtains the JAXBContext from the given type, by using the cache if possible.

      We don't use locks to control access to cache, but this code should be thread-safe thanks to the immutable JAXB.Cache and volatile.

      Throws:
      JAXBException
    • unmarshal

      public static <T> T unmarshal(File xml, Class<T> type)
      Reads in a Java object tree from the given XML input.
      Parameters:
      xml - Reads the entire file as XML.
    • unmarshal

      public static <T> T unmarshal(URL xml, Class<T> type)
      Reads in a Java object tree from the given XML input.
      Parameters:
      xml - The resource pointed by the URL is read in its entirety.
    • unmarshal

      public static <T> T unmarshal(URI xml, Class<T> type)
      Reads in a Java object tree from the given XML input.
      Parameters:
      xml - The URI is turned into URL and then follows the handling of URL.
    • unmarshal

      public static <T> T unmarshal(String xml, Class<T> type)
      Reads in a Java object tree from the given XML input.
      Parameters:
      xml - The string is first interpreted as an absolute URI. If it's not a valid absolute URI, then it's interpreted as a File
    • unmarshal

      public static <T> T unmarshal(InputStream xml, Class<T> type)
      Reads in a Java object tree from the given XML input.
      Parameters:
      xml - The entire stream is read as an XML infoset. Upon a successful completion, the stream will be closed by this method.
    • unmarshal

      public static <T> T unmarshal(Reader xml, Class<T> type)
      Reads in a Java object tree from the given XML input.
      Parameters:
      xml - The character stream is read as an XML infoset. The encoding declaration in the XML will be ignored. Upon a successful completion, the stream will be closed by this method.
    • unmarshal

      public static <T> T unmarshal(Source xml, Class<T> type)
      Reads in a Java object tree from the given XML input.
      Parameters:
      xml - The XML infoset that the Source represents is read.
    • toSource

      private static Source toSource(Object xml) throws IOException
      Creates Source from various XML representation. See unmarshal(java.io.File, java.lang.Class<T>) for the conversion rules.
      Throws:
      IOException
    • marshal

      public static void marshal(Object jaxbObject, File xml)
      Writes a Java object tree to XML and store it to the specified location.
      Parameters:
      jaxbObject - The Java object to be marshalled into XML. If this object is a JAXBElement, it will provide the root tag name and the body. If this object has XmlRootElement on its class definition, that will be used as the root tag name and the given object will provide the body. Otherwise, the root tag name is inferred from the short class name. This parameter must not be null.
      xml - XML will be written to this file. If it already exists, it will be overwritten.
      Throws:
      DataBindingException - If the operation fails, such as due to I/O error, unbindable classes.
    • marshal

      public static void marshal(Object jaxbObject, URL xml)
      Writes a Java object tree to XML and store it to the specified location.
      Parameters:
      jaxbObject - The Java object to be marshalled into XML. If this object is a JAXBElement, it will provide the root tag name and the body. If this object has XmlRootElement on its class definition, that will be used as the root tag name and the given object will provide the body. Otherwise, the root tag name is inferred from the short class name. This parameter must not be null.
      xml - The XML will be sent to the resource pointed by this URL. Note that not all URLs support such operation, and exact semantics depends on the URL implementations. In case of HTTP URLs, this will perform HTTP POST.
      Throws:
      DataBindingException - If the operation fails, such as due to I/O error, unbindable classes.
    • marshal

      public static void marshal(Object jaxbObject, URI xml)
      Writes a Java object tree to XML and store it to the specified location.
      Parameters:
      jaxbObject - The Java object to be marshalled into XML. If this object is a JAXBElement, it will provide the root tag name and the body. If this object has XmlRootElement on its class definition, that will be used as the root tag name and the given object will provide the body. Otherwise, the root tag name is inferred from the short class name. This parameter must not be null.
      xml - The URI is turned into URL and then follows the handling of URL. See above.
      Throws:
      DataBindingException - If the operation fails, such as due to I/O error, unbindable classes.
    • marshal

      public static void marshal(Object jaxbObject, String xml)
      Writes a Java object tree to XML and store it to the specified location.
      Parameters:
      jaxbObject - The Java object to be marshalled into XML. If this object is a JAXBElement, it will provide the root tag name and the body. If this object has XmlRootElement on its class definition, that will be used as the root tag name and the given object will provide the body. Otherwise, the root tag name is inferred from the short class name. This parameter must not be null.
      xml - The string is first interpreted as an absolute URI. If it's not a valid absolute URI, then it's interpreted as a File
      Throws:
      DataBindingException - If the operation fails, such as due to I/O error, unbindable classes.
    • marshal

      public static void marshal(Object jaxbObject, OutputStream xml)
      Writes a Java object tree to XML and store it to the specified location.
      Parameters:
      jaxbObject - The Java object to be marshalled into XML. If this object is a JAXBElement, it will provide the root tag name and the body. If this object has XmlRootElement on its class definition, that will be used as the root tag name and the given object will provide the body. Otherwise, the root tag name is inferred from the short class name. This parameter must not be null.
      xml - The XML will be sent to the given OutputStream. Upon a successful completion, the stream will be closed by this method.
      Throws:
      DataBindingException - If the operation fails, such as due to I/O error, unbindable classes.
    • marshal

      public static void marshal(Object jaxbObject, Writer xml)
      Writes a Java object tree to XML and store it to the specified location.
      Parameters:
      jaxbObject - The Java object to be marshalled into XML. If this object is a JAXBElement, it will provide the root tag name and the body. If this object has XmlRootElement on its class definition, that will be used as the root tag name and the given object will provide the body. Otherwise, the root tag name is inferred from the short class name. This parameter must not be null.
      xml - The XML will be sent as a character stream to the given Writer. Upon a successful completion, the stream will be closed by this method.
      Throws:
      DataBindingException - If the operation fails, such as due to I/O error, unbindable classes.
    • marshal

      public static void marshal(Object jaxbObject, Result xml)
      Writes a Java object tree to XML and store it to the specified location.
      Parameters:
      jaxbObject - The Java object to be marshalled into XML. If this object is a JAXBElement, it will provide the root tag name and the body. If this object has XmlRootElement on its class definition, that will be used as the root tag name and the given object will provide the body. Otherwise, the root tag name is inferred from the short class name. This parameter must not be null.
      xml - The XML will be sent to the Result object.
      Throws:
      DataBindingException - If the operation fails, such as due to I/O error, unbindable classes.
    • _marshal

      private static void _marshal(Object jaxbObject, Object xml)
      Writes a Java object tree to XML and store it to the specified location.

      This method is a convenience method that combines several basic operations in the JAXBContext and Marshaller. This method is designed to be the preferred method for developers new to Jakarta XML Binding. This method has the following characteristics:

      1. Generally speaking, the performance is not necessarily optimal. It is expected that those people who need to write performance critical code will use the rest of the Jakarta XML Binding API directly.
      2. Errors that happen during the processing is wrapped into DataBindingException (which will have JAXBException as its cause. It is expected that those people who prefer the checked exception would use the rest of the Jakarta XML Binding API directly.
      Parameters:
      jaxbObject - The Java object to be marshalled into XML. If this object is a JAXBElement, it will provide the root tag name and the body. If this object has XmlRootElement on its class definition, that will be used as the root tag name and the given object will provide the body. Otherwise, the root tag name is inferred from the short class name. This parameter must not be null.
      xml - Represents the receiver of XML. Objects of the following types are allowed.
      Allowed Objects
      Type Operation
      File XML will be written to this file. If it already exists, it will be overwritten.
      URL The XML will be sent to the resource pointed by this URL. Note that not all URLs support such operation, and exact semantics depends on the URL implementations. In case of HTTP URLs, this will perform HTTP POST.
      URI The URI is turned into URL and then follows the handling of URL. See above.
      String The string is first interpreted as an absolute URI. If it's not a valid absolute URI, then it's interpreted as a File
      OutputStream The XML will be sent to the given OutputStream. Upon a successful completion, the stream will be closed by this method.
      Writer The XML will be sent as a character stream to the given Writer. Upon a successful completion, the stream will be closed by this method.
      Result The XML will be sent to the Result object.
      Throws:
      DataBindingException - If the operation fails, such as due to I/O error, unbindable classes.
    • inferName

      private static String inferName(Class<?> clazz)
    • toResult

      private static Result toResult(Object xml) throws IOException
      Creates Result from various XML representation. See _marshal(Object,Object) for the conversion rules.
      Throws:
      IOException