nbsp; }
}
} catch (Exception e)
{
System.out.println(e); } } public
static void main(String[] args) { XMLParser parser = new XMLParser
(); parser.getAllUserNames("c:\\test.xml"); }
} package net.viralpatel.java.xmlparser;import java.io.File;import javax.xml.parsers.DocumentBuilder;import
javax.xml.parsers.DocumentBuilderFactory;import org.w3c.dom.Document;import org.w3c.dom.Element;import
org.w3c.dom.Node;import org.w3c.dom.NodeList;public class XMLParser {public void getAllUserNames(String fileName) {try
{DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();DocumentBuilder db =
dbf.newDocumentBuilder();File file = new File
(fileName);if (file.exists())
{Document doc = db.parse
(file);Element docEle = doc.getDocumentElement();// Print root element of the
documentSystem.out.println("Root element of the
document: "+ docEle.getNodeName());NodeList studentList = docEle.getElementsByTagName("student");// Print total student elements in
documentSystem.outnb
sp;.println("Total students: " + studentList.getLength());if (studentList != null
studentList.getLength() 0) {for (int i = 0; i
studentList.getLength(); i++) {Node node = studentList.item(i);if (node.getNodeType() == Node.ELEMENT_NODE) {System.out .println("=====================");Element e = (Element)
node;NodeList nodeList = e.getElementsByTagName
("name");System.out.println("Name:
"+ nodeList.item(0).getChildNodes().item(0)
.getNodeValue());nodeList = e.getElementsByTagName
("grade");System.out.println("Grade:
"+ nodeList.item(0).getChildNodes().item(0)
.getNodeValue());nodeList = e.getElementsByTagName
("age");System.out.println("Age:
"+ nodeList.item(0).getChildNodes().item(0)
.getNodeValue());}
}} else
{System.exit(1);}
}} catch (Exception e)
{System.out.println(e);}}
public static void main(String[] args) {XMLParser parser = new XMLParser
();parser.getAllUserNames("c:\\test.xml");}}17.
Convert Array to Map in Javaimport java.util.Map; import
org.apachemons.lang.ArrayUtils; public class Main
{ public static void main(String[] args)
{ String[][] countries = { { "United States",
"New York" }, { "United Kingdom", "London" }, {
"Netherland", "Amsterdam" }, { "Japan", "Tokyo" }, { "France", "Paris" } }; Map countryCapitals =
ArrayUtils.toMap(countries); System.out.println("Capital of Japan is " + countryCapitals.get
("Japan")); System.out.println("Capital of
France is " + countryCapitals.get("France")); }
} import java.util.Map;import org.apachemons.lang.ArrayUtils;public class Main {public static void main(String[] args) {String[][]
countries = { { "United States", "New York" }, { "United Kingdom", "London" },{ "Netherland",
"Amsterdam" }, { "Japan", "Tokyo" }, { "France", "Paris" } };Map countryCapitals = ArrayUtils.toMap(countries);System.out.println("Capital of Japan is " +
countryCapitals.get("Japan"));System.out.println("Capital of
France is " + countryCapitals.get("France"));}}18. Send Email
using Javaimport javax.mail.*; import
javax.mail.internet.*; import java.util.*; public void postMail( String recipients[ ], String subject, String message ,
String from) throws MessagingException {
boolean debug = false; //Set the host smtp address
Properties props = new Properties();
props.put("mail.smtp.host",
"smtp.example"); // create some
properties and get the default Session Session
session = Session.getDefaultInstance(props, null);
session.setDebug(debug); // create a message Message msg = new MimeMessage(session); // set the from and to address
InternetAddress addressFrom = new InternetAddress
(from); msg.setFrom(addressFrom);
InternetAddress[] addressTo = new
InternetAddress[recipients.length]; for (int i =
0; i recipients.length; i++) {
addressTo = new InternetAddress
(recipients); }
msg.setRecipients(Message.RecipientType.TO,
addressTo); // Optional : You can
also set your custom headers in the Email if you Want
msg.addHeader("MyHeaderName", "myHeaderValue");
// Setting the Subject and Content
Type msg.setSubject(subject);
msg.setContent(message, "text/plain");
Transport.send(msg); } import javax.mail.*;import javax.mail.internet.*;import
java.util.*;public void postMail( String recipients[ ], String subject, String message ,
String from) throws MessagingException{boolean debug =
false;//Set the host smtp addressProperties props = new Properties();props.put
("mail.smtp.host", "smtp.example");// create some properties and get the default
SessionSession session = Session.getDefaultInstance(props,
null);session.setDebug(debug);// create a messageMessage msg = new
MimeMessage(session);// set the from and to addressInternetAddress addressFrom = new InternetAddress(from);msg.setFrom(addressFrom);InternetAddress[] addressTo = new InternetAddress
[recipients.length];for (int i = 0; i
recipients.length; i++){addressTo = new InternetAddress
(recipients);}msg.setRecipients
(Message.RecipientType.TO, addressTo);// Optional : You can also set your custom headers in the
Email if you Wantmsg.addHeader("MyHeaderName",
"myHeaderValue");// Setting the Subject and Content Typemsg.setSubject(subject);msg.setContent(message,
"text/plain");Transport.send(msg);}19. Send HTTP
request fetching data using Javaimport java.io.BufferedReader; import
java.io.InputStreamReader; import java.URL;
public class Main { public static
void main(String[] args) {
try {
URL my_url =
new URL("xasxt/mysql/mysql5.1/");nbs
p; BufferedReader br = new BufferedReader(new InputStreamReader(my_url.openStream()));
String
strTemp = "";
while(null
!= (strTemp = br.readLine())){
System.out.println(strTemp);
}
} catch (Exception ex) {
ex.printStackTrace(); }
} } import java.io.BufferedReader;import
java.io.InputStreamReader;import java.URL;public class Main {public static void main(String[] args)
{try {URL my_url = new URL(xasxt/mysql/mysql5.1/); BufferedReader br = new BufferedReader(new InputStreamReader(my_url.openStream()));String strTemp =
"";while(null != (strTemp = br.readLine()))
{System.out.println(strTemp);}
} catch (Exception ex) {ex.printStackTrace
();}}}20. Resize an Array in Java/** * Reallocates an array with a new size, and copies the
contents * of the old array to the new array. * @param
oldArray the old array, to be reallocated. * @param
newSize the new array size. *
@return A new array with the
same contents. */ private static Object resizeArray (Object
oldArray, int newSize) { int oldSize =
java.lang.reflect.Array.getLength(oldArray); Class
elementType = oldArray.getClass().getComponentType(); Object newArray = java.lang.reflect.Array.newInstance(
elementType,newSize); int preserveLength = Math.min
(oldSize,newSize); if (preserveLength 0)
System.arraycopy
(oldArray,0,newArray,0,preserveLength); return
newArray; } // Test routine for
resizeArray(). public static void main (String[] args)
{ int[] a = {1,2,3}; a =
(int[])resizeArray(a,5); a[3] = 4;
a[4] = 5; for (int i=0; i System.out.println (a);
}文章由斐格整理，收集辛苦，希望能保留出处，谢谢斑竹大哥。
