Java operation XML (using org. W3C. DOM)

1. Create a DOM

Xmlbuilder. java is used to create the Dom, root Node /************************************* * ******************************** Project name: rochoc <p> * package name: rochoc. XML. compile <p> * file name: xmlbuilder <p> * Writer: luoc <p> * Writing Date: 2005-6-22 <p> * program function (class) Description: generate document and root nodes based on the imported XML file <p> ** program change date: * Author: * description of changes: **************************************** * ***************************/package rochoc. XML. imports; import Java. io. file; import Java. io. ioexception; import javax. XML. parsers. documentbuilder; import javax. XML. parsers. documentbuilderfactory; import javax. XML. parsers. parserconfigurationexception; import Org. apache. log4j. logger; import Org. w3C. dom. document; import Org. w3C. dom. element; import Org. XML. sax. saxexception;/*** Class Name: xmlbuilder <p> * class description: generate the document and root nodes based on the imported XML file <p> * Prepared: luoc <p> * written on: 2005-6-22 <p> * main public member variables: <p> * Main public method: <p> **/public class xmlbuilder {/*** constructor Description: <p> * parameter description: @ Param path <p> **/Public xmlbuilder (string path) {This. path = path; Init ();}/*** Method Name: init <p> * method function: initialization function <p> * parameter description: <p> * return: void <p> * Author: luoc * Date: 2005-6-22 **/Public void Init () {builddocument (); buildroot ();}/*** Method Name: builddocument <p> * method function: generate document from XML file <p> * parameter description: <p> * return: void <p> * Author: luoc * Date: 2005-6-22 **/ Private void builddocument () {documentbuilderfactory factory = documentbuilderfactory. newinstance (); try {documentbuilder builder = factory. newdocumentbuilder (); logger. debug ("construct document builder success. "); Doc = builder. parse (new file (PATH); logger. debug ("build XML document success. ");} catch (parserconfigurationexception e) {logger. error ("construct document builder error:" + E);} catch (saxex Ception e) {logger. error ("Parse XML file error:" + E);} catch (ioexception e) {logger. error ("read XML file error:" + E) ;}/ *** Method Name: buildroot <p> * method function: generate xml root node <p> * parameter description: <p> * return: void <p> * Author: luoc * Date: 2005-6-22 **/private void buildroot () {root = Doc. getdocumentelement ();}/*** @ return returns the doc. */Public document getdoc () {return Doc;}/*** @ Param Doc the doc to be set. */Public void setdoc (document DOC) {this.doc = Doc;}/*** @ return returns path. */Public String getpath () {return path;}/*** @ Param path the path to be set. */Public void setpath (string path) {This. Path = path;}/*** @ return returns root. */Public element getroot () {return root;}/*** @ Param root the root to be set. */Public void setroot (element root) {This. root = root;}/* global variable */private string Path = NULL; // XML file path private document DOC = NULL; // document private element root = NULL for the XML file; // The root node of the XML file private logger = logger. getlogger (getclass (). getname ());}

2. Search, insert, delete, and modify

Xmloper. java is used to operate XML files, including searching, adding, deleting, and modifying nodes /****************************** * ************************************ Project name: rochoc <p> * package name: rochoc. XML. compile <p> * file name: xmloper <p> * Prepared by: luoc <p> * written on: 2005-6-22 <p> * program function (class) Description: perform read and write operations on XML <p> ** program change date: * Author: * Change description: **************************************** * ***************************/package rochoc. XML. imports; import Java. util. arraylist; import Org. apache. log4j. logger; import Org. w3C. dom. document; import Org. w3C. dom. element; import Org. w3C. dom. node; import Org. w3C. dom. nodelist;/*** Class Name: xmloper <p> * class description: read/write operations on XML files, all static functions <p> * Prepared: luoc <p> * Writing Date: 2005-6-22 <p> * main public member variable: <p> * main public method: <p> **/public class xmloper {/*** constructor Description: <p> * parameter description: <p> **/private xmloper () {}/*** Method Name: getnodelist <p> * method function: obtains all child nodes of the parent node parent. <p> * parameter description: @ Param parent * parameter description: @ return <p> * return: nodelist <p> * Author: luoc * Date: 2005-6-22 **/public static nodelist getnodelist (element parent) {return parent. getchildnodes ();}/*** Method Name: getelementsbyname <p> * method function: query the node set with the specified name in the parent node <p> * parameter description: @ Param parent * parameter description: @ Param name * parameter description: @ return <p> * return: Element [] <p> * Author: luoc * Date: 2005-6-22 **/public static element [] getelementsbyname (element parent, string name) {arraylist reslist = new arraylist (); nodelist NL = getnodelist (parent ); for (INT I = 0; I <NL. getlength (); I ++) {node nD = NL. item (I); If (Nd. getnodename (). equals (name) {reslist. add (ND) ;}} element [] res = new element [reslist. size ()]; for (INT I = 0; I <reslist. size (); I ++) {res [0] = (element) reslist. get (I);} logger. debug (parent. getnodename () + "'s children of" + name + "'s num:" + Res. length); Return res;}/*** Method Name: getelementname <p> * method function: get the name of the specified Element <p> * parameter description: @ Param element * parameter description: @ return <p> * return: String <p> * Author: luoc * Date: 2005-6-22 **/public static string getelementname (element) {return element. getnodename ();}/*** Method Name: getelementvalue <p> * method function: Get the value of a specified Element <p> * parameter description: @ Param element * parameter description: @ return <p> * return: String <p> * Author: luoc * Date: 2005-6-22 **/public static string getelementvalue (element) {nodelist NL = element. getchildnodes (); For (INT I = 0; I <NL. getlength (); I ++) {If (NL. item (I ). getnodetype () = node. text_node) // is a text node {logger. debug (element. getnodename () + "has a text node. "); Return element. getfirstchild (). getnodevalue () ;}} logger. error (element. getnodename () + "hasn' t a text node. "); return NULL;}/*** Method Name: getelementattr <p> * method function: gets the ATTR value of the attribute of the specified Element <p> * parameter description: @ Param element * parameter description: @ Param ATTR * parameter description: @ return <p> * return: String <p> * Author: luoc * Date: 2005-6-22 **/public static string getelementattr (element, string ATTR) {return element. getattribute (ATTR);}/*** Method Name: setelementvalue <p> * method function: set the value of a specified Element <p> * parameter description: @ Param element * parameter description: @ Param Val <p> * return: void <p> * Author: luoc * Date: 2005-6-22 **/public static void setelementvalue (element, string Val) {node = element. getownerdocument (). createtextnode (VAL); nodelist NL = element. getchildnodes (); For (INT I = 0; I <NL. getlength (); I ++) {node nD = NL. item (I); If (Nd. getnodetype () = node. text_node) // is a text node {nd. setnodevalue (VAL); logger. debug ("modify" + element. getnodename () + "'s node value succe. "); Return ;}} logger. debug ("new" + element. getnodename () + "'s node value succe. "); element. appendchild (node);}/*** Method Name: setelementattr <p> * method function: Set the attribute of the node element <p> * parameter description: @ Param element * parameter description: @ Param ATTR * parameter description: @ Param attrval <p> * return: void <p> * Author: luoc * Date: 2005-6-22 **/public static void setelementattr (element, string ATTR, string attrval) {element. setattribute (ATTR, attrval);}/*** Method Name: addelement <p> * method function: Add node child under parent <p> * parameter description: @ Param parent * parameter description: @ Param child <p> * return: void <p> * Author: luoc * Date: 2005-6-22 **/public static void addelement (element parent, element child) {parent. appendchild (child);}/*** Method Name: addelement <p> * method function: add the node generated by the string tagname under the parent <p> * parameter description: @ Param parent * parameter description: @ Param tagname <p> * return: void <p> * Author: luoc * Date: 2005-6-22 **/public static void addelement (element parent, string tagname) {document DOC = parent. getownerdocument (); element child = Doc. createelement (tagname); parent. appendchild (child);}/*** Method Name: addelement <p> * method function: add the text node of tagname under parent, and the value is text <p> * parameter description: @ Param parent * parameter description: @ Param tagname * parameter description: @ Param text <p> * return: void <p> * Author: luoc * Date: 2005-6-22 **/public static void addelement (element parent, string tagname, string text) {document DOC = parent. getownerdocument (); element child = Doc. createelement (tagname); setelementvalue (child, text); parent. appendchild (child);}/*** Method Name: removeelement <p> * method function: Remove a node named tagname under the parent node. <p> * parameter description: @ Param parent * parameter description: @ Param tagname <p> * return: void <p> * Author: luoc * Date: 2005-6-22 **/public static void removeelement (element parent, string tagname) {logger. debug ("Remove" + parent. getnodename () + "'s children by tagname" + tagname + "begin... "); nodelist NL = parent. getchildnodes (); For (INT I = 0; I <NL. getlength (); I ++) {node nD = NL. item (I); If (Nd. getnodename (). equals (tagname) {parent. removechild (ND); logger. debug ("remove child" + Nd + "'success. ") ;}} logger. debug ("Remove" + parent. getnodename () + "'s children by tagname" + tagname + "end. ");}/* global variable */static logger = logger. getlogger ("xmloper ");}

3. Create an XML file

Xmlcreater. java is used to create an XML file /********************************** * *********************************** Project name: rochoc <p> * package name: rochoc. XML. compile <p> * file name: xmlcreater <p> * Prepared by: luoc <p> * written on: 2005-6-22 <p> * program function (class) Description: create Dom and generate xml file <p> ** program change date: * Change Author: * Change description: **************************************** * ***************************/package rochoc. XML. imports; import Java. io. file; import javax. XML. parsers. Documentbuilder; import javax. XML. parsers. documentbuilderfactory; import javax. XML. parsers. parserconfigurationexception; import javax. XML. transform. transformer; import javax. XML. transform. transformerconfigurationexception; import javax. XML. transform. transformerexception; import javax. XML. transform. transformerfactory; import javax. XML. transform. dom. domsource; import javax. XML. transform. stream. streamresult; Import Org. apache. log4j. logger; import Org. w3C. dom. document; import Org. w3C. dom. element;/*** Class Name: xmlcreater <p> * class description: Creates a Dom and generates an XML file <p> * Writer: luoc <p> * Writing Date: 2005-6-22 <p> * main public member variables: <p> * main public method: <p> **/public class xmlcreater {/*** constructor description: <p> * parameter description: @ Param path: XML file path <p> **/Public xmlcreater (string path) {This. path = path; Init ();}/*** Method Name: init <p> * method function: initialization function <p> * parameter description: <p> * return: Void <p> * Author: luoc * Date: 2005-6-22 **/private void Init () {documentbuilderfactory factory = documentbuilderfactory. newinstance (); try {documentbuilder builder = factory. newdocumentbuilder (); Doc = builder. newdocument (); // new Dom} catch (parserconfigurationexception e) {logger. error ("parse Dom builder error:" + E) ;}/ *** Method Name: createrootelement <p> * method function: Create a root node, <p> * parameter description: @ Param roottagname <p> * is returned: Element <p> * Author: luoc * Date: 2005-6-22 **/public element createrootelement (string roottagname) {If (Doc. getdocumentelement () = NULL) {logger. debug ("create root element" + roottagname + "'success. "); element root = Doc. createelement (roottagname); Doc. appendchild (Root); Return root;} logger. warn ("this Dom's root element is exist, create fail. "); Return Doc. getdocumentelement ();}/*** Method Name: createelemen T <p> * method function: add a sub-node tagname under the parent node <p> * parameter description: @ Param parent * parameter description: @ Param tagname <p> * return: element <p> * Author: luoc * Date: 2005-6-22 **/public element createelement (element parent, string tagname) {document DOC = parent. getownerdocument (); element child = Doc. createelement (tagname); parent. appendchild (child); return child;}/*** Method Name: createelement <p> * method function: tabname <p> * parameter description: @ Param Parent * parameter description: @ Param tagname * parameter description: @ Param value <p> * return: Element <p> * Author: luoc * Date: 2005-6-22 **/public element createelement (element parent, string tagname, string value) {document DOC = parent. getownerdocument (); element child = Doc. createelement (tagname); xmloper. setelementvalue (child, value); parent. appendchild (child); return child;}/*** Method Name: createattribute <p> * method function: Add attribute under the parent node <p> * parameter description: @ Param parent * parameter description: @ Param attrname attribute name * parameter description: @ Param attrvalue attribute value <p> * return: void <p> * Author: luoc * Date: 2005-6-22 **/Public void createattribute (element parent, string attrname, string attrvalue) {xmloper. setelementattr (parent, attrname, attrvalue);}/*** Method Name: buildxmlfile <p> * method function: generate an XML file based on Dom <p> * parameter description: <p> * return: void <p> * Author: luoc * Date: 2005-6-22 **/Public void buildxmlfile () {transformerfactory Tfactory = transformerfactory. newinstance (); try {transformer = tfactory. newtransformer (); domsource source = new domsource (DOC); logger. debug ("New domsource success. "); streamresult result = new streamresult (new file (PATH); logger. debug ("New streamresult success. "); transformer. setoutputproperty ("encoding", "GBK"); transformer. transform (source, result); logger. debug ("build XML file '" + path +" 'Success. ");} catch (transformerconfigurationexception e) {logger. error ("create transformer error:" + E);} catch (transformerexception e) {logger. error ("transformer XML file error:" + E) ;}/ *** @ return returns the doc. */Public document getdoc () {return Doc;}/*** @ Param Doc the doc to be set. */Public void setdoc (document DOC) {this.doc = Doc;}/*** @ return returns path. */Public String getpath () {return path;}/*** @ Param path the path to be set. */Public void setpath (string path) {This. path = path;}/* global variable */private logger = logger. getlogger (getclass (). getname (); private document DOC = NULL; // the newly created Dom private string Path = NULL; // The generated XML file absolute path}