--- schema_version: "1" id: 7082a07ce3b5c0b59c8bc3534dea30c8ebaa4fbb722bbd394c7bb50816326476 title: XmlStreamWriter Class collection: legacydeveloper version: current locale: en-us portal_url: https://docs.salesforce.com/legacydeveloper/current/en-us/apexref/apex_classes_xml_XmlStream_writer.md canonical_url: https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_classes_xml_XmlStream_writer.htm source_site: developer.salesforce.com content_type: documentation content_hash: 5855a44ee58a49e29aaf2f5142c4ef8f226247b7b1dfbf3c60c463dd57c36fd9 description: The XmlStreamWriter class provides methods for writing XML data.Creates a new instance of the XmlStreamWriter class.Closes this instance of an XmlStreamWriter and free any resources associated with it.Returns the XML written by the XmlStreamWriter instance.Binds the specified URI to the default namespace. This URI is bound in the scope of the current START_ELEMENT – END_ELEMENT pair.Writes an attribute to the output stream.Writes the specified CData to the output stream.Writes the specified text to the output stream.Writes the specified comment to the output stream.Writes the specified namespace to the output stream.Writes an empty element tag to the output stream.Closes any start tags and writes corresponding end tags to the output stream.Writes an end tag to the output stream, relying on the internal state of the writer to determine the prefix and local name.Writes the specified namespace to the output stream.Writes the specified processing instruction.Writes the XML Declaration using the specified XML encoding and version.Writes the start tag specified by localName to the output stream. --- # XmlStreamWriter Class The XmlStreamWriter class provides methods for writing XML data. ## Namespace [System](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_namespace_System.htm "The System namespace provides classes and methods for core Apex functionality.") ## Usage You can use the XmlStreamWriter class to programmatically construct an XML document, then use HTTP classes to send the document to an external server. The XmlStreamWriter class is similar to the XMLStreamWriter utility class from StAX (Streaming API for XML). StAX is an API to read and write XML documents, originating from the Java programming language community. ![Note](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/images/icon_note.png) #### Note The XmlStreamWriter class in Apex is based on its counterpart in Java. See [Java XMLStreamWriter class](http://docs.oracle.com/javase/6/docs/api/javax/xml/stream/XMLStreamWriter.html "html (New Window)"). - **[XmlStreamWriter Constructors](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_classes_xml_XmlStream_writer.htm#apex_System_XmlStreamWriter_constructors)** - **[XmlStreamWriter Methods](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_classes_xml_XmlStream_writer.htm#apex_System_XmlStreamWriter_methods)** #### See Also - [Http Class](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_classes_restful_http_http.htm#apex_classes_restful_http_http "Use the Http class to initiate an HTTP request and response.") - [HttpRequest Class](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_classes_restful_http_httprequest.htm#apex_classes_restful_http_httprequest "Use the HttpRequest class to programmatically create HTTP requests like GET, POST, PATCH, PUT, and DELETE.") - [HttpResponse Class](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_classes_restful_http_httpresponse.htm#apex_classes_restful_http_httpresponse "Use the HttpResponse class to handle the HTTP response returned by the Http class.") ## XmlStreamWriter Constructors The following are constructors for XmlStreamWriter. - **[XmlStreamWriter()](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_classes_xml_XmlStream_writer.htm#apex_System_XmlStreamWriter_ctor)** Creates a new instance of the XmlStreamWriter class. ### XmlStreamWriter() Creates a new instance of the XmlStreamWriter class. #### Signature public XmlStreamWriter() ## XmlStreamWriter Methods The following are methods for XmlStreamWriter. All are instance methods. - **[close()](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_classes_xml_XmlStream_writer.htm#apex_System_XmlStreamWriter_close)** Closes this instance of an XmlStreamWriter and free any resources associated with it. - **[getXmlString()](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_classes_xml_XmlStream_writer.htm#apex_System_XmlStreamWriter_getXmlString)** Returns the XML written by the XmlStreamWriter instance. - **[setDefaultNamespace(uri)](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_classes_xml_XmlStream_writer.htm#apex_System_XmlStreamWriter_setDefaultNamespace)** Binds the specified URI to the default namespace. This URI is bound in the scope of the current START\_ELEMENT – END\_ELEMENT pair. - **[writeAttribute(prefix, namespaceUri, localName, value)](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_classes_xml_XmlStream_writer.htm#apex_System_XmlStreamWriter_writeAttribute)** Writes an attribute to the output stream. - **[writeCData(data)](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_classes_xml_XmlStream_writer.htm#apex_System_XmlStreamWriter_writeCData)** Writes the specified CData to the output stream. - **[writeCharacters(text)](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_classes_xml_XmlStream_writer.htm#apex_System_XmlStreamWriter_writeCharacters)** Writes the specified text to the output stream. - **[writeComment(comment)](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_classes_xml_XmlStream_writer.htm#apex_System_XmlStreamWriter_writeComment)** Writes the specified comment to the output stream. - **[writeDefaultNamespace(namespaceUri)](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_classes_xml_XmlStream_writer.htm#apex_System_XmlStreamWriter_writeDefaultNamespace)** Writes the specified namespace to the output stream. - **[writeEmptyElement(prefix, localName, namespaceUri)](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_classes_xml_XmlStream_writer.htm#apex_System_XmlStreamWriter_writeEmptyElement)** Writes an empty element tag to the output stream. - **[writeEndDocument()](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_classes_xml_XmlStream_writer.htm#apex_System_XmlStreamWriter_writeEndDocument)** Closes any start tags and writes corresponding end tags to the output stream. - **[writeEndElement()](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_classes_xml_XmlStream_writer.htm#apex_System_XmlStreamWriter_writeEndElement)** Writes an end tag to the output stream, relying on the internal state of the writer to determine the prefix and local name. - **[writeNamespace(prefix, namespaceUri)](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_classes_xml_XmlStream_writer.htm#apex_System_XmlStreamWriter_writeNamespace)** Writes the specified namespace to the output stream. - **[writeProcessingInstruction(target, data)](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_classes_xml_XmlStream_writer.htm#apex_System_XmlStreamWriter_writeProcessingInstruction)** Writes the specified processing instruction. - **[writeStartDocument(encoding, version)](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_classes_xml_XmlStream_writer.htm#apex_System_XmlStreamWriter_writeStartDocument)** Writes the XML Declaration using the specified XML encoding and version. - **[writeStartElement(prefix, localName, namespaceUri)](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_classes_xml_XmlStream_writer.htm#apex_System_XmlStreamWriter_writeStartElement)** Writes the start tag specified by localName to the output stream. ### close() Closes this instance of an XmlStreamWriter and free any resources associated with it. #### Signature public Void close() #### Return Value Type: Void ### getXmlString() Returns the XML written by the XmlStreamWriter instance. #### Signature public String getXmlString() #### Return Value Type: [String](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_string.htm#apex_methods_system_string "Contains methods for the String primitive data type.") ### setDefaultNamespace(uri) Binds the specified URI to the default namespace. This URI is bound in the scope of the current START\_ELEMENT – END\_ELEMENT pair. #### Signature public Void setDefaultNamespace(String uri) #### Parameters - **uri**: Type: [String](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_string.htm#apex_methods_system_string "Contains methods for the String primitive data type.") #### Return Value Type: Void ### writeAttribute(prefix, namespaceUri, localName, value) Writes an attribute to the output stream. #### Signature public Void writeAttribute(String prefix, String namespaceUri, String localName, String value) #### Parameters - **prefix**: Type: [String](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_string.htm#apex_methods_system_string "Contains methods for the String primitive data type.") - **namespaceUri**: Type: [String](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_string.htm#apex_methods_system_string "Contains methods for the String primitive data type.") - **localName**: Type: [String](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_string.htm#apex_methods_system_string "Contains methods for the String primitive data type.") Specifies the name of the attribute. - **value**: Type: [String](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_string.htm#apex_methods_system_string "Contains methods for the String primitive data type.") #### Return Value Type: Void ### writeCData(data) Writes the specified CData to the output stream. #### Signature public Void writeCData(String data) #### Parameters - **data**: Type: [String](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_string.htm#apex_methods_system_string "Contains methods for the String primitive data type.") #### Return Value Type: Void ### writeCharacters(text) Writes the specified text to the output stream. #### Signature public Void writeCharacters(String text) #### Parameters - **text**: Type: [String](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_string.htm#apex_methods_system_string "Contains methods for the String primitive data type.") #### Return Value Type: Void ### writeComment(comment) Writes the specified comment to the output stream. #### Signature public Void writeComment(String comment) #### Parameters - **comment**: Type: [String](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_string.htm#apex_methods_system_string "Contains methods for the String primitive data type.") #### Return Value Type: Void ### writeDefaultNamespace(namespaceUri) Writes the specified namespace to the output stream. #### Signature public Void writeDefaultNamespace(String namespaceUri) #### Parameters - **namespaceUri**: Type: [String](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_string.htm#apex_methods_system_string "Contains methods for the String primitive data type.") #### Return Value Type: Void ### writeEmptyElement(prefix, localName, namespaceUri) Writes an empty element tag to the output stream. #### Signature public Void writeEmptyElement(String prefix, String localName, String namespaceUri) #### Parameters - **prefix**: Type: [String](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_string.htm#apex_methods_system_string "Contains methods for the String primitive data type.") - **localName**: Type: [String](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_string.htm#apex_methods_system_string "Contains methods for the String primitive data type.") Specifies the name of the tag to be written. - **namespaceUri**: Type: [String](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_string.htm#apex_methods_system_string "Contains methods for the String primitive data type.") #### Return Value Type: Void ### writeEndDocument() Closes any start tags and writes corresponding end tags to the output stream. #### Signature public Void writeEndDocument() #### Return Value Type: Void ### writeEndElement() Writes an end tag to the output stream, relying on the internal state of the writer to determine the prefix and local name. #### Signature public Void writeEndElement() #### Return Value Type: Void ### writeNamespace(prefix, namespaceUri) Writes the specified namespace to the output stream. #### Signature public Void writeNamespace(String prefix, String namespaceUri) #### Parameters - **prefix**: Type: [String](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_string.htm#apex_methods_system_string "Contains methods for the String primitive data type.") - **namespaceUri**: Type: [String](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_string.htm#apex_methods_system_string "Contains methods for the String primitive data type.") #### Return Value Type: Void ### writeProcessingInstruction(target, data) Writes the specified processing instruction. #### Signature public Void writeProcessingInstruction(String target, String data) #### Parameters - **target**: Type: [String](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_string.htm#apex_methods_system_string "Contains methods for the String primitive data type.") - **data**: Type: [String](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_string.htm#apex_methods_system_string "Contains methods for the String primitive data type.") #### Return Value Type: Void ### writeStartDocument(encoding, version) Writes the XML Declaration using the specified XML encoding and version. #### Signature public Void writeStartDocument(String encoding, String version) #### Parameters - **encoding**: Type: [String](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_string.htm#apex_methods_system_string "Contains methods for the String primitive data type.") - **version**: Type: [String](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_string.htm#apex_methods_system_string "Contains methods for the String primitive data type.") #### Return Value Type: Void ### writeStartElement(prefix, localName, namespaceUri) Writes the start tag specified by localName to the output stream. #### Signature public Void writeStartElement(String prefix, String localName, String namespaceUri) #### Parameters - **prefix**: Type: [String](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_string.htm#apex_methods_system_string "Contains methods for the String primitive data type.") - **localName**: Type: [String](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_string.htm#apex_methods_system_string "Contains methods for the String primitive data type.") - **namespaceUri**: Type: [String](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_string.htm#apex_methods_system_string "Contains methods for the String primitive data type.") #### Return Value Type: Void