雖然考慮到讀取文件會(huì)影響性能，最終沒有采用這種方式，而是取數(shù)據(jù)庫，但總結(jié)出來以后說不定用的著，呵呵. 1，下載dom4j 2，寫xml的代碼   public?class?AddPictureAction?extends?BaseAction? {
 ????public?ActionForward?execute(ActionMapping?mapping,?ActionForm?form,?HttpServletRequest?request,
  ????????????HttpServletResponse?response)?throws?DocumentException?{
????????try?{
????????????FileWriter?out?=?new?FileWriter(request.getSession().getServletContext().getRealPath(Constants.DOG_SON_HOT_PICTURE));
??????????????//這里我用的相對(duì)路徑，代碼里是"WEB-INF//config/a.xml"
????????????String?picPath1?=?request.getParameter("picPath1");
????????????String?picPath2?=?request.getParameter("picPath2");
????????????String?picPath3?=?request.getParameter("picPath3");
????????????String?picPath4?=?request.getParameter("picPath4");
????????????String?picPath5?=?request.getParameter("picPath5");
????????????String?url1?=?request.getParameter("url1");
????????????String?url2?=?request.getParameter("url2");
????????????String?url3?=?request.getParameter("url3");
????????????String?url4?=?request.getParameter("url4");
????????????String?url5?=?request.getParameter("url5");
????????????Document?document?=?DocumentHelper.createDocument();
????????????Element?root?=?document.addElement("root");
????????????root.addElement("picPath1").addText(picPath1);
????????????root.addElement("picPath2").addText(picPath2);
????????????root.addElement("picPath3").addText(picPath3);
????????????root.addElement("picPath4").addText(picPath4);
????????????root.addElement("picPath5").addText(picPath5);
????????????root.addElement("url1").addText(url1);
????????????root.addElement("url2").addText(url2);
????????????root.addElement("url3").addText(url3);
????????????root.addElement("url4").addText(url4);
????????????root.addElement("url5").addText(url5);
????????????document.write(out);
????????????out.close();
????????}?catch?(IOException?e)?{
????????????e.printStackTrace();
 ????????}
????????return?mapping.findForward(Constants.SUCCESS);
????}
 }解析xml的代碼  ????????Resource?resource?=?new
????????????????????FileSystemResource(request.getSession().getServletContext().getRealPath(Constants.DOG_SON_HOT_PICTURE));
????????SAXReader?reader?=?new?SAXReader();
????????Document?document?=?reader.read(resource.getInputStream());
????????System.out.println(document.asXML());
Parsing?XML
One?of?the?first?things?you'll?probably?want?to?do?is?to?parse?an?XML?document?of?some?kind.?This?is?easy?to?do?in?dom4j.?The?following?code?demonstrates?how?to?this.?
import?java.net.URL;
import?org.dom4j.Document;
import?org.dom4j.DocumentException;
import?org.dom4j.io.SAXReader;
public?class?Foo?{
????public?Document?parse(URL?url)?throws?DocumentException?{
????????SAXReader?reader?=?new?SAXReader();
????????Document?document?=?reader.read(url);
????????return?document;
????}
}
Using?Iterators
A?document?can?be?navigated?using?a?variety?of?methods?that?return?standard?Java?Iterators.?For?example?
????public?void?bar(Document?document)?throws?DocumentException?{
????????Element?root?=?document.getRootElement();
????????//?iterate?through?child?elements?of?root
????????for?(?Iterator?i?=?root.elementIterator();?i.hasNext();?)?{
????????????Element?element?=?(Element)?i.next();
????????????//?do?something
????????}
????????//?iterate?through?child?elements?of?root?with?element?name?"foo"
????????for?(?Iterator?i?=?root.elementIterator(?"foo"?);?i.hasNext();?)?{
????????????Element?foo?=?(Element)?i.next();
????????????//?do?something
????????}
????????//?iterate?through?attributes?of?root?
????????for?(?Iterator?i?=?root.attributeIterator();?i.hasNext();?)?{
????????????Attribute?attribute?=?(Attribute)?i.next();
????????????//?do?something
????????}
?????}
Powerful?Navigation?with?XPath
In?dom4j?XPath?expressions?can?be?evaluated?on?the?Document?or?on?any?Node?in?the?tree?(such?as?Attribute,?Element?or?ProcessingInstruction).?This?allows?complex?navigation?throughout?the?document?with?a?single?line?of?code.?For?example.?
????public?void?bar(Document?document)?{
????????List?list?=?document.selectNodes(?"//foo/bar"?);
????????Node?node?=?document.selectSingleNode(?"//foo/bar/author"?);
????????String?name?=?node.valueOf(?"@name"?);
????}
For?example?if?you?wish?to?find?all?the?hypertext?links?in?an?XHTML?document?the?following?code?would?do?the?trick.?
????public?void?findLinks(Document?document)?throws?DocumentException?{
????????List?list?=?document.selectNodes(?"//a/@href"?);
????????for?(Iterator?iter?=?list.iterator();?iter.hasNext();?)?{
????????????Attribute?attribute?=?(Attribute)?iter.next();
????????????String?url?=?attribute.getValue();
????????}
????}
If?you?need?any?help?learning?the?XPath?language?we?highly?recommend?the?Zvon?tutorial?which?allows?you?to?learn?by?example.?
Fast?Looping
If?you?ever?have?to?walk?a?large?XML?document?tree?then?for?performance?we?recommend?you?use?the?fast?looping?method?which?avoids?the?cost?of?creating?an?Iterator?object?for?each?loop.?For?example?
????public?void?treeWalk(Document?document)?{
????????treeWalk(?document.getRootElement()?);
????}
????public?void?treeWalk(Element?element)?{
????????for?(?int?i?=?0,?size?=?element.nodeCount();?i?<?size;?i++?)?{
????????????Node?node?=?element.node(i);
????????????if?(?node?instanceof?Element?)?{
????????????????treeWalk(?(Element)?node?);
????????????}
????????????else?{
????????????????//?do?something.
????????????}
????????}
????}
Creating?a?new?XML?document
Often?in?dom4j?you?will?need?to?create?a?new?document?from?scratch.?Here's?an?example?of?doing?that.?
import?org.dom4j.Document;
import?org.dom4j.DocumentHelper;
import?org.dom4j.Element;
public?class?Foo?{
????public?Document?createDocument()?{
????????Document?document?=?DocumentHelper.createDocument();
????????Element?root?=?document.addElement(?"root"?);
????????Element?author1?=?root.addElement(?"author"?)
????????????.addAttribute(?"name",?"James"?)
????????????.addAttribute(?"location",?"UK"?)
????????????.addText(?"James?Strachan"?);
????????
????????Element?author2?=?root.addElement(?"author"?)
????????????.addAttribute(?"name",?"Bob"?)
????????????.addAttribute(?"location",?"US"?)
????????????.addText(?"Bob?McWhirter"?);
????????return?document;
????}
}
Writing?a?document?to?a?file
A?quick?and?easy?way?to?write?a?Document?(or?any?Node)?to?a?Writer?is?via?the?write()?method.?
??FileWriter?out?=?new?FileWriter(?"foo.xml"?);
??document.write(?out?);
If?you?want?to?be?able?to?change?the?format?of?the?output,?such?as?pretty?printing?or?a?compact?format,?or?you?want?to?be?able?to?work?with?Writer?objects?or?OutputStream?objects?as?the?destination,?then?you?can?use?the?XMLWriter?class.?
import?org.dom4j.Document;
import?org.dom4j.io.OutputFormat;
import?org.dom4j.io.XMLWriter;
public?class?Foo?{
????public?void?write(Document?document)?throws?IOException?{
????????//?lets?write?to?a?file
????????XMLWriter?writer?=?new?XMLWriter(
????????????new?FileWriter(?"output.xml"?)
????????);
????????writer.write(?document?);
????????writer.close();
????????//?Pretty?print?the?document?to?System.out
????????OutputFormat?format?=?OutputFormat.createPrettyPrint();
????????writer?=?new?XMLWriter(?System.out,?format?);
????????writer.write(?document?);
????????//?Compact?format?to?System.out
????????format?=?OutputFormat.createCompactFormat();
????????writer?=?new?XMLWriter(?System.out,?format?);
????????writer.write(?document?);
????}
}
Converting?to?and?from?Strings
If?you?have?a?reference?to?a?Document?or?any?other?Node?such?as?an?Attribute?or?Element,?you?can?turn?it?into?the?default?XML?text?via?the?asXML()?method.?
????????Document?document?=?;
????????String?text?=?document.asXML();
If?you?have?some?XML?as?a?String?you?can?parse?it?back?into?a?Document?again?using?the?helper?method?DocumentHelper.parseText()?
????????String?text?=?"<person>?<name>James</name>?</person>";
????????Document?document?=?DocumentHelper.parseText(text);
Styling?a?Document?with?XSLT
Applying?XSLT?on?a?Document?is?quite?straightforward?using?the?JAXP?API?from?Sun.?This?allows?you?to?work?against?any?XSLT?engine?such?as?Xalan?or?SAXON.?Here?is?an?example?of?using?JAXP?to?create?a?transformer?and?then?applying?it?to?a?Document.?
import?javax.xml.transform.Transformer;
import?javax.xml.transform.TransformerFactory;
import?org.dom4j.Document;
import?org.dom4j.io.DocumentResult;
import?org.dom4j.io.DocumentSource;
public?class?Foo?{
????public?Document?styleDocument(
????????Document?document,?
????????String?stylesheet
????)?throws?Exception?{
????????//?load?the?transformer?using?JAXP
????????TransformerFactory?factory?=?TransformerFactory.newInstance();
????????Transformer?transformer?=?factory.newTransformer(?
????????????new?StreamSource(?stylesheet?)?
????????);
????????//?now?lets?style?the?given?document
????????DocumentSource?source?=?new?DocumentSource(?document?);
????????DocumentResult?result?=?new?DocumentResult();
????????transformer.transform(?source,?result?);
????????//?return?the?transformed?document
????????Document?transformedDoc?=?result.getDocument();
????????return?transformedDoc;
????}
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