Reading & writting code for XML doc

Question

I need help with writting a java code that will read the XML dopcument below & output it as given below. thanks.
<?xml version="1.0"?>
<!-- Employee expenses by department. -->
<firm>
<!-- Hmmm, suspicious. -->
<dept name="Accounting">
<emp name="Boswell" amt="437.46" />
<emp name="Austen" amt="124.07" />
<emp name="Johnson" amt="184.19" />
<emp name="Boswell" amt="423.99" />
<emp name="Keats" amt="321.14" />
</dept>
<!-- Why so much travel and always to Russia in summer? -->
<dept name="Finance">
<emp name="Tolstoi" amt="224.46" />
<emp name="Turgenev" amt="532.11" />
<emp name="Tolstoi" amt="149.08" />
<emp name="Gogal" amt="643.26" />
<emp name="Tolstoi" amt="265.91" />
</dept>
<!-- Marketing, smarketing -->
<dept name="Marketing">
<emp name="Mishima" amt="754.18" />
<emp name="Kawabata" amt="398.07" />
<emp name="Kawabata" amt="398.07" />
</dept>
<!-- High pay, high stress: deserve to travel -->
<dept name="Technology">
<emp name="Hesse" amt="156.44" />
<emp name="Handke" amt="174.21" />
<emp name="Hesse" amt="365.21" />
<emp name="Hesse" amt="452.33" />
</dept>
</firm>
OUTPUT:
Accounting
Austen --> $124.07
Bosworth --> $861.45
Johnson --> $184.19
Keats --> $321.14
Finance
Gogal --> $643.26
Tolstoi --> $639.45
Turgenev --> $532.11
Marketing
Kawabata --> $796.14
Mishima --> $754.18
Technology
Handke --> $174.21
Hesse --> $973.98
----------------------------------------------------

Answer 1

/* INTERFACE */
import java.util.*;
import java.util.regex.*;
abstract public interface XMLInterface {
abstract public void parse(String file_name);
abstract public String getStartTag(String item);
abstract public String getEndTag(String item);
abstract public Map getAttributes(String item);
abstract public int getXMLType(String item);
public static final String start_tagSA =
"<[\\s]*[\\w]+[\\s]*>";
public static final String end_tagSA =
"</[\\s]*[\\w]+[\\s]*>";
public static final String pi =
"<\\?[\\W\\w\\s]*\\?>";
public static final String comment =
"<!--[\\s]*[\\W\\w]+[\\s]*-->";
public static final String elementSA =
"<[\\s]*[\\w\\W]+[\\s]*[]?>";
public static final String attribute =
"[:\\w]+[\\s]*=[\\s]*([\\'|\"])[\\w\\d\\.$\\s]+\\1";
public static final int XML_BAD_TYPE = 0;
public static final int XML_COMMENT = -1;
public static final int XML_ELEMENT = -2;
public static final int XML_PI = -3;
public static final int XML_START_TAG = -4;
public static final int XML_END_TAG = -5;
/* IMPLIMENTATION */
import java.io.*;
import java.util.*;
import java.util.regex.*;
public class ParserXML implements XMLInterface {
public void parse(String file_name) {
readFile(file_name);
compile_patterns();
Iterator it = records.iterator();
while (it.hasNext()) {
String next = (String) it.next();
int type = getXMLType(next = next.trim());
switch (type) {
case XMLInterface.XML_START_TAG:
System.out.println("Start tag: " + next);
String tag = getStartTag(next);
if (tag != null)
System.out.println("\tTag is " + tag);
break;
case XMLInterface.XML_END_TAG:
System.out.println("End tag: " + next);
break;
case XMLInterface.XML_ELEMENT:
System.out.println("Element: " + next);
Map m = getAttributes(next);
if (m != null) {
Set s = m.keySet();
Iterator iter = s.iterator();
while (iter.hasNext()) {
Object key = iter.next();
System.out.println("\tAttribute: " + key + " = " + m.get(key));
break;
case XMLInterface.XML_COMMENT:
System.out.println("Comment: " + next);
break;
case XMLInterface.XML_PI:
System.out.println("Processing instruction: " + next);
break;
default:
System.out.println("Bad XML type: " + next);
break;
public int getXMLType(String item) {
Matcher m = null;
m = start_tagSA.matcher(item);
if (m.matches()) return XMLInterface.XML_START_TAG;
m = end_tagSA.matcher(item);
if (m.matches()) return XMLInterface.XML_END_TAG;
m = elementSA.matcher(item);
if (m.matches()) return XMLInterface.XML_ELEMENT;
m = comment.matcher(item);
if (m.matches()) return XMLInterface.XML_COMMENT;
m = pi.matcher(item);
if (m.matches()) return XMLInterface.XML_PI;
return XMLInterface.XML_BAD_TYPE;
public String getStartTag(String item) {
Matcher m = start_tagSA.matcher(item);
if (m.find())
return m.group();
else
return null;
public String getEndTag(String item) {
return null;
public Map getAttributes(String item) {
Matcher m = attribute.matcher(item);
if (!m.find()) return null;
m.reset();
Map attributes = new HashMap();
int n = 0;
while (m.find(n)) {
String[ ] key_value = m.group().split("=");
attributes.put(key_value[0].trim(), key_value[1].trim());
n = m.end();
return attributes;
private void readFile(String filename) {
records = new ArrayList();
try {
BufferedReader input = new BufferedReader(new FileReader(filename));
String record = null;
while ((record = input.readLine()) != null)
records.add(record);
input.close();
catch(Exception e) {
e.printStackTrace();
System.exit(-1);
private void dump() {
Iterator it = records.iterator();
while (it.hasNext())
System.out.println(it.next());
private void compile_patterns() {
elementSA = Pattern.compile(XMLInterface.elementSA);
comment = Pattern.compile(XMLInterface.comment);
pi = Pattern.compile(XMLInterface.pi);
start_tagSA = Pattern.compile(XMLInterface.start_tagSA);
end_tagSA = Pattern.compile(XMLInterface.end_tagSA);
attribute = Pattern.compile(XMLInterface.attribute);
private List records;
private Pattern elementSA;
private Pattern comment;
private Pattern pi;
private Pattern start_tagSA;
private Pattern end_tagSA;
private Pattern attribute;
/* DRIVER */
class ParseDriver {
public static void main(String[ ] args) {
if (args.length < 1) {
System.out.println("ParseDriver <filename>");
return;
ParserXML parser = new ParserXML();
parser.parse(args[0]);