Java generates indentation and line feed for XML

Dom the following code uses Dom to generate an XML document

Package XML; </P> <p> Import Java. io. file; <br/> Import Java. io. filenotfoundexception; <br/> Import Java. io. fileoutputstream; </P> <p> Import javax. XML. parsers. documentbuilder; <br/> Import javax. XML. parsers. documentbuilderfactory; <br/> Import javax. XML. parsers. parserconfigurationexception; <br/> Import javax. XML. transform. transformer; <br/> Import javax. XML. transform. transformerconfigurationexception; <br/> Import javax. XML. transform. transformerexception; <br/> Import javax. XML. transform. transformerfactory; <br/> Import javax. XML. transform. dom. domsource; <br/> Import javax. XML. transform. stream. streamresult; </P> <p> Import Org. w3C. dom. document; <br/> Import Org. w3C. dom. element; </P> <p> public class xmlhandler {<br/> Public void createxml () throws filenotfoundexception {<br/> document DOC = NULL; <br/> documentbuilderfactory DBF = documentbuilderfactory. newinstance (); </P> <p> try {<br/> documentbuilder docbuilder = DBF. newdocumentbuilder (); <br/> Doc = docbuilder. newdocument (); <br/> element root = Doc. createelement ("root"); <br/> Doc. appendchild (Root); </P> <p> element Country = Doc. createelement ("contry"); <br/> country. appendchild (Doc. createtextnode ("China"); <br/> root. appendchild (country); </P> <p> element city = Doc. createelement ("city"); <br/> city. appendchild (Doc. createtextnode ("Beijing"); <br/> country. appendchild (city); </P> <p> city = Doc. createelement ("city"); <br/> city. appendchild (Doc. createtextnode ("Shanghai"); <br/> country. appendchild (city); </P> <p> transformerfactory TF = transformerfactory. newinstance (); <br/> transformer = TF. newtransformer (); <br/> file = new file ("E: // cities. XML "); <br/> fileoutputstream out = new fileoutputstream (File); <br/> streamresult xmlresult = new streamresult (out); <br/> transformer. transform (New domsource (DOC), xmlresult); <br/>} catch (parserconfigurationexception e) {<br/> E. printstacktrace (); <br/>} catch (transformerconfigurationexception e) {<br/> E. printstacktrace (); <br/>} catch (transformerexception e) {<br/> E. printstacktrace (); <br/>} catch (filenotfoundexception e) {<br/> E. printstacktrace (); <br/> throw E; <br/>}</P> <p> Public static void main (string ARGs []) {<br/> xmlhandler XH = new xmlhandler (); <br/> try {<br/> XH. createxml (); <br/>} catch (filenotfoundexception e) {<br/> E. printstacktrace (); <br/>}< br/>

 

The generated XML is as follows:
<? XML version = "1.0" encoding = "UTF-8"?> <Country> <China> <city> Beijing </city> <city> Shanghai </city> </China> </country>

All XML content is in a row without line breaks or indentation.

Now in the code

Transformer transformer = TF. newtransformer ();

Add

Transformer. setoutputproperty (outputkeys. indent, "yes ");

 

Generate xml again

 <? XML version = "1.0" encoding = "UTF-8"?> <Br/> <country> <br/> <China> <br/> <city> Beijing </city> <br/> <city> Shanghai </city> <br /> </China> <br/> </country>

This time there is a line break, but there is still no indentation. For this reason, I have searched Google and Baidu for many times and have not found a solution. It may be because I have or have no patience, so I tried to solve it. Add a space in front

Element. appendchild (Doc. createtextnode ("/N "));

The final code is

Package XML; </P> <p> Import Java. io. file; <br/> Import Java. io. filenotfoundexception; <br/> Import Java. io. fileoutputstream; </P> <p> Import javax. XML. parsers. documentbuilder; <br/> Import javax. XML. parsers. documentbuilderfactory; <br/> Import javax. XML. parsers. parserconfigurationexception; <br/> Import javax. XML. transform. outputkeys; <br/> Import javax. XML. transform. transformer; <br/> Import javax. XML. transform. transformerconfigurationexception; <br/> Import javax. XML. transform. transformerexception; <br/> Import javax. XML. transform. transformerfactory; <br/> Import javax. XML. transform. dom. domsource; <br/> Import javax. XML. transform. stream. streamresult; </P> <p> Import Org. w3C. dom. document; <br/> Import Org. w3C. dom. element; </P> <p> public class xmlhandler {<br/> Public void createxml () throws filenotfoundexception {<br/> document DOC = NULL; <br/> documentbuilderfactory DBF = documentbuilderfactory. newinstance (); </P> <p> try {<br/> documentbuilder docbuilder = DBF. newdocumentbuilder (); <br/> Doc = docbuilder. newdocument (); </P> <p> element Country = Doc. createelement ("country"); </P> <p> Doc. appendchild (country); </P> <p> country. appendchild (Doc. createtextnode ("/N"); </P> <p> element China = Doc. createelement ("China"); <br/> country. appendchild (China); </P> <p> China. appendchild (Doc. createtextnode ("/N"); </P> <p> element city = Doc. createelement ("city"); <br/> city. appendchild (Doc. createtextnode ("Beijing"); <br/> China. appendchild (city); </P> <p> China. appendchild (Doc. createtextnode ("/N"); </P> <p> city = Doc. createelement ("city"); <br/> city. appendchild (Doc. createtextnode ("Shanghai"); <br/> China. appendchild (city); </P> <p> China. appendchild (Doc. createtextnode ("/N"); </P> <p> transformerfactory TF = transformerfactory. newinstance (); <br/> transformer = TF. newtransformer (); <br/> file = new file ("E: // cities. XML "); <br/> fileoutputstream out = new fileoutputstream (File); <br/> streamresult xmlresult = new streamresult (out); <br/> transformer. setoutputproperty (outputkeys. indent, "yes"); <br/> transformer. transform (New domsource (DOC), xmlresult); <br/>} catch (parserconfigurationexception e) {<br/> E. printstacktrace (); <br/>} catch (transformerconfigurationexception e) {<br/> E. printstacktrace (); <br/>} catch (transformerexception e) {<br/> E. printstacktrace (); <br/>} catch (filenotfoundexception e) {<br/> E. printstacktrace (); <br/> throw E; <br/>}</P> <p> Public static void main (string ARGs []) {<br/> xmlhandler XH = new xmlhandler (); <br/> try {<br/> XH. createxml (); <br/>} catch (filenotfoundexception e) {<br/> E. printstacktrace (); <br/>}< br/>

The generated XML is

<? XML version = "1.0" encoding = "UTF-8"?> <Br/> <country> <br/> <China> <br/> <city> Beijing </city> <br/> <city> Shanghai </city> <br /> </China> <br/> </country>

 

Ii. generate xml with Sax and line feed indent

Package XML; </P> <p> Import Java. io. fileoutputstream; <br/> Import Java. io. stringwriter; </P> <p> Import javax. XML. transform. outputkeys; <br/> Import javax. XML. transform. result; <br/> Import javax. XML. transform. transformer; <br/> Import javax. XML. transform. transformerconfigurationexception; <br/> Import javax. XML. transform. sax. saxtransformerfactory; <br/> Import javax. XML. transform. sax. transformerhandler; <br/> Import javax. XML. transform. stream. streamresult; </P> <p> Import Org. XML. sax. saxexception; <br/> Import Org. XML. sax. helpers. attributesimpl; </P> <p> public class xmlhandler {</P> <p> Public String createxmlfile () {<br/> string xmlstr = NULL; <br/> try {<br/> result resultxml = new streamresult (New fileoutputstream ("E: // cities. XML "); <br/> stringwriter writerstr = new stringwriter (); <br/> saxtransformerfactory SFF = (saxtransformerfactory) saxtransformerfactory. newinstance (); <br/> transformerhandler th = SFF. newtransformerhandler (); <br/> transformer = th. gettransformer (); <br/> transformer. setoutputproperty (outputkeys. encoding, "UTF-8"); <br/> th. setresult (resultxml); <br/> th. startdocument (); <br/> attributesimpl ATTR = new attributesimpl (); <br/> th. startelement ("", "", "country", ATTR); <br/> th. startelement ("", "", "China", ATTR); </P> <p> th. startelement ("", "", "city", ATTR); <br/> string bj = "Beijing"; <br/> th. characters (BJ. tochararray (), 0, BJ. length (); <br/> th. endelement ("", "", "city"); </P> <p> th. startelement ("", "", "city", ATTR); <br/> string SH = "Shanghai"; <br/> th. characters (Sh. tochararray (), 0, Sh. length (); <br/> th. endelement ("", "", "city"); </P> <p> th. endelement ("", "", "China"); <br/> th. endelement ("", "", "country"); <br/> th. enddocument (); <br/> xmlstr = writerstr. getbuffer (). tostring (); <br/>}catch (transformerconfigurationexception e) {<br/> E. printstacktrace (); <br/>}catch (saxexception e) {<br/> E. printstacktrace (); <br/>}catch (exception e) {<br/> E. printstacktrace (); <br/>}< br/> return xmlstr; <br/>}</P> <p> Public static void main (string ARGs []) {<br/> xmlhandler XH = new xmlhandler (); <br/> XH. createxmlfile (); <br/>}< br/>

The XML generated using Sax is as follows:

<? XML version = "1.0" encoding = "UTF-8"?> <Country> <China> <city> Beijing </city> <city> Shanghai </city> </China> </country>

There are no line breaks or indentation.

Add

Transformer. setoutputproperty (outputkeys. indent, "yes ");

The generated XML has a line break but is not indented.

<? XML version = "1.0" encoding = "UTF-8"?> <Br/> <country> <br/> <China> <br/> <city> Beijing </city> <br/> <city> Shanghai </city> <br /> </China> <br/> </country> <br/>

Similarly, add a space according to the DOM method.

String four = "/N"; <br/> transformerhandler. characters (four. tochararray (), 0, four. Length ());

The final sax code is as follows:

Package XML; </P> <p> Import Java. io. fileoutputstream; <br/> Import Java. io. stringwriter; </P> <p> Import javax. XML. transform. outputkeys; <br/> Import javax. XML. transform. result; <br/> Import javax. XML. transform. transformer; <br/> Import javax. XML. transform. transformerconfigurationexception; <br/> Import javax. XML. transform. sax. saxtransformerfactory; <br/> Import javax. XML. transform. sax. transformerhandler; <br/> Import javax. XML. transform. stream. streamresult; </P> <p> Import Org. XML. sax. saxexception; <br/> Import Org. XML. sax. helpers. attributesimpl; </P> <p> public class xmlhandler {</P> <p> Public String createxmlfile () {<br/> string xmlstr = NULL; <br/> try {<br/> result resultxml = new streamresult (New fileoutputstream ("E: // cities. XML "); <br/> stringwriter writerstr = new stringwriter (); <br/> saxtransformerfactory SFF = (saxtransformerfactory) saxtransformerfactory. newinstance (); <br/> transformerhandler th = SFF. newtransformerhandler (); <br/> transformer = th. gettransformer (); <br/> transformer. setoutputproperty (outputkeys. indent, "yes"); <br/> transformer. setoutputproperty (outputkeys. encoding, "UTF-8"); <br/> th. setresult (resultxml); <br/> th. startdocument (); <br/> string four = "/N"; <br/> string eight = "/N"; <br/> attributesimpl ATTR = new attributesimpl (); </P> <p> th. startelement ("", "", "country", ATTR); </P> <p> th. characters (four. tochararray (), 0, four. length (); </P> <p> th. startelement ("", "", "China", ATTR); </P> <p> th. characters (eight. tochararray (), 0, eight. length (); </P> <p> th. startelement ("", "", "city", ATTR); <br/> string bj = "Beijing"; <br/> th. characters (BJ. tochararray (), 0, BJ. length (); <br/> th. endelement ("", "", "city"); </P> <p> th. characters (eight. tochararray (), 0, eight. length (); </P> <p> th. startelement ("", "", "city", ATTR); <br/> string SH = "Shanghai"; <br/> th. characters (Sh. tochararray (), 0, Sh. length (); <br/> th. endelement ("", "", "city"); </P> <p> th. characters (four. tochararray (), 0, four. length (); </P> <p> th. endelement ("", "", "China"); <br/> th. endelement ("", "", "country"); <br/> th. enddocument (); <br/> xmlstr = writerstr. getbuffer (). tostring (); <br/>}catch (transformerconfigurationexception e) {<br/> E. printstacktrace (); <br/>}catch (saxexception e) {<br/> E. printstacktrace (); <br/>}catch (exception e) {<br/> E. printstacktrace (); <br/>}< br/> return xmlstr; <br/>}</P> <p> Public static void main (string ARGs []) {<br/> xmlhandler XH = new xmlhandler (); <br/> XH. createxmlfile (); <br/>}< br/>

Generated XML

<? XML version = "1.0" encoding = "UTF-8"?> <Br/> <country> <br/> <China> <br/> <city> Beijing </city> <br/> <city> Shanghai </city> <br /> </China> <br/> </country>