XML conversion to map general algorithm implementation (Stax implementation)

The current project needs to convert XML to map, and the following gives its own code implementation. Ask the great gods to provide better code implementations.

Scene:

XML text strings need to be parsed in the project, and XML text strings need to be mapped to objects in map format.

Demand:

1, in order to improve performance, need to use Stax to parse

2, map structure inside need to support list, map, string three data format

Example:

Example one: * string:<name>burceliu</name><age>18</age> * converted to the map structure: {age=18, Name=burceliu}

Example two: * string:<student><name>burceliu</name><age>18</age></student> * converted to the map structure: { Student={age=18, Name=burceliu}}

Example three: * String: <student><name>burceliu</name><age>18</age></student><student ><name>BurceLi</name><age>28</age></student> * converted to the map structure: {student=[{age=18, name =burceliu}, {age=28, name=burceli}]}

Example four: * String: <students><student><name>burceliu</name><age>18</age></student ><student><name>BurceLi</name><age>28</age></student></students> * Map structure converted to: {students={student=[{age=18, Name=burceliu}, {age=28, Name=burceli}]}}

Example five: * string:<str>str1</str><str>str2</str><str>str3</str> * converted to the map structure: {STR=[STR1 , STR2, STR3]}

Code implementation

Defines the parsing interface, providing 2 core methods

Public interface Ixmlparser {/** * XML format string converted to MAP * @param XML * @return */public map<string, object> Parse (string x ML);/** * Initialization action * can set initialization action, such as root node name, */public void Init ();}

Implementation class, using Stax technology to realize the scheme

Package Com.juxtapose.xml.parser;import Java.io.stringreader;import Java.util.arraylist;import java.util.HashMap; Import Java.util.list;import Java.util.map;import Java.util.concurrent.atomic.atomicinteger;import Javax.xml.stream.xmlinputfactory;import Javax.xml.stream.xmlstreamconstants;import javax.xml.stream.xmlstreamreader;/** * XML string Parser implementation class .<br> * XML string converted to map object .<br> * Converted data type is map, List, String three data Types .<br> * * @author Burceliu (mailto:[email protected]) */public class Xmlparserstaximpl  Implements Ixmlparser {public static final string node_element_name = "root";p ublic static final string Node_default_value = "";p rivate string rootname;//root node private string defaultnullvalue;//node without value default private static Xmlinputfactory factory = Xmlinputfactory.newinstance ();    static {Factory.setproperty (Xmlinputfactory.is_namespace_aware, Boolean.false);  Factory.setproperty (xmlinputfactory.is_coalescing, boolean.true); }/* (non-javadoc) * @see Com.juxtapose.xml.parser.IXMLParsEr#parse (java.lang.String) */public map<string, object> parse (String xml) {map<string, object> Map = new Hash Map<string, object> (); StringReader StringReader = Null;try{stringreader = new StringReader (XML);  Xmlstreamreader reader = Factory.createxmlstreamreader (StringReader); Map = parse (reader); catch (Throwable t) {throw new runtimeexception (t);}        Finally{if (null! = StringReader) {try {stringreader.close ();} catch (Exception e) {throw new RuntimeException (e);}}}    return map; }/* (non-javadoc) * @see com.juxtapose.xml.parser.ixmlparser#init () */public void init () {if (this.getrootname () = = null) {this.setrootname (node_element_name); This.setdefaultnullvalue (Node_default_value);}} @SuppressWarnings ({"Unchecked", "rawtypes"}) private map<string, object> parse (Xmlstreamreader reader) throws throwable{map<string, object> Map = new hashmap<string, object> (); map<string, object> currentmap = map;int event = Reader.geteventtype (); List<string> NAMes = new arraylist<string> ();        Nodeamount nodeamount = new Nodeamount (); int taglength = 0;        String tagName = null; String Tagvalue = This.defaultnullvalue;while (true) {switch (event) {case Xmlstreamconstants.star              T_document:break;            Case XMLStreamConstants.START_ELEMENT:tagValue = This.defaultnullvalue;            TagName = Reader.getlocalname ();            if (This.rootName.equals (TagName)) {break;            } names.add (TagName);                        taglength++;            Currentmap = map; if (Taglength > 1) {for (int i=0;i< taglength-1;i++) {Object object = Currentmap.get (Names.get (i            ));            if (null = = object) {object = new hashmap<string, object> ();            Currentmap.put (Names.get (i), object);            Currentmap = (map<string, object>) Object; }else{int currenttagnamesize = Nodeamount. getsize (i + 1 + "" + names.get (i));            if (Currenttagnamesize > 1) {if (object instanceof Map) {List parentlist = new ArrayList ();            Parentlist.add (object);            Map Tempmap = new HashMap ();            Parentlist.add (TEMPMAP);            Currentmap.put (Names.get (i), parentlist);            Currentmap = Tempmap;            }else if (object instanceof list) {List parentlist = (list) object;            int parentlistsize = Parentlist.size ();            if (parentlistsize! = currenttagnamesize) {Map tempmap = new HashMap ();            Parentlist.add (TEMPMAP);            Currentmap = Tempmap;            }else{Map Tempmap = (map) parentlist.get (Parentlist.size ()-1);            Currentmap = Tempmap;            }}}else{Currentmap = (map<string, object>) Object;              }}}} Nodeamount.add (Names.size () + tagName);  Break                 Case XMLStreamConstants.CHARACTERS:tagValue = Reader.gettext ();            Break            Case XMLStreamConstants.END_ELEMENT:tagName = Reader.getlocalname ();            if (This.rootName.equals (TagName)) {break;            } currentmap = map; if (Taglength > 1) {for (int i=0;i< taglength-1;i++) {Object object = Currentmap.get (Names.get (i            )); if (null = = object) {//nothing to do}else{if (object instanceof list) {list Li            St = (List) object;            Currentmap = (Map) list.get (List.size ()-1);            }else if (object instanceof Map) {currentmap = (map) object;            }}}} Object OldValue = Currentmap.get (tagName);            if (!currentmap.containskey (TagName)) {currentmap.put (tagName, Tagvalue); Nodeamount.remove (Names.size () + tagName);            }else{if (oldValue instanceof list) {List List = (list) OldValue;            if (list.size () > 0) {Object obj = list.get (0);            if (obj instanceof String) {(List) oldValue). Add (Tagvalue);            Nodeamount.remove (names.size () + tagName); }}}else if (OldValue instanceof Map) {}else{List tmplist = new A            Rraylist ();            Currentmap.put (TagName, tmplist);            Tmplist.add (OldValue);            Tmplist.add (Tagvalue);            Nodeamount.remove (names.size () + tagName);            }} tagvalue = This.defaultnullvalue;            Names.remove (Names.size ()-1);                taglength--;              Break              Case XMLStreamConstants.END_DOCUMENT:break;              } if (!reader.hasnext ()) {break; } event =Reader.next (); }return map;} Public String Getrootname () {return rootname;} public void Setrootname (String rootname) {this.rootname = Rootname;} Public String Getdefaultnullvalue () {return defaultnullvalue;} public void Setdefaultnullvalue (String defaultnullvalue) {this.defaultnullvalue = Defaultnullvalue;} Class Nodeamount{private map<string, atomicinteger> Map =new hashmap<string, atomicinteger> ();p ublic void Add (String nodeName) {Atomicinteger integer = Map.get (NodeName), if (null = = integer) {integer = new Atomicinteger (0); Map.put (NodeName, Integer);} Integer.incrementandget ();} public void Remove (String nodeName) {Atomicinteger integer = Map.get (nodeName); if (null! = integer) { Integer.decrementandget ();}} public int GetSize (String nodeName) {Atomicinteger integer = Map.get (nodeName); if (null = = integer) {integer = new atomicint Eger (0); Map.put (NodeName, Integer);} return Integer.intvalue ();}}} /* Change history * $Log $ */

Unit tests:

Package Test.com.juxtapose.xml.parser;import Java.util.map;import Org.junit.after;import org.junit.AfterClass; Import Org.junit.before;import Org.junit.beforeclass;import Org.junit.test;import Com.juxtapose.xml.parser.ixmlparser;import com.juxtapose.xml.parser.xmlparserstaximpl;/** * * @author Burceliu ( Mailto:[email protected]) */public class Testxmlparserstaximpl {/** * @throws java.lang.Exception */@ Beforeclasspublic static void Setupbeforeclass () throws Exception {}/** * @throws java.lang.Exception */@ Afterclasspublic static void Teardownafterclass () throws Exception {}/** * @throws java.lang.Exception */@Beforepublic VO ID setUp () throws Exception {}/** * @throws java.lang.Exception */@Afterpublic void TearDown () throws Exception {} @Testpub LIC void Test () {ixmlparser parser = new Xmlparserstaximpl ();p arser.init (); String XML = "<root><student><name>burceliu</name><age>18</age></student ></root> "; map<string, object> result = PArser.parse (XML); SYSTEM.OUT.PRINTLN (result); XML = "<root><student><name>burceliu</name><age>18</ Age></student><student><name>burceli</name><age>28</age></student ></root> result = Parser.parse (XML); SYSTEM.OUT.PRINTLN (result); XML = "<root><str>str1</str><str>str2</str><str> Str3</str></root> "; result = Parser.parse (XML); SYSTEM.OUT.PRINTLN (result); XML = "<root><students><student><name>BurceLiu</name> <age>18</age></student><student><name>burceli</name><age>28</age ></student></students></root> result = Parser.parse (XML); SYSTEM.OUT.PRINTLN (result); XML = "<root><name>burceliu</name><age>18</age></ Root> "; result = Parser.parse (XML); SYSTEM.OUT.PRINTLN (result);}} /* Change history * $Log $ */

Observe the output of the console:

{student={age=18, Name=burceliu}} {student=[{age=18, Name=burceliu}, {age=28, name=burceli}]} {str=[str1, str2, STR3]} {students={student=[{age=18, Name=burceliu}, {age=28, Name=burceli}]}} {age=18, Name=burceliu}

XML conversion to map general algorithm implementation (Stax implementation)