16. 解析/讀取XML 文件
XML文件
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 | <?xmlversion="1.0"?> <students> <student> <name>John</name> <grade>B</grade> <age>12</age> </student> <student> <name>Mary</name> <grade>A</grade> <age>11</age> </student> <student> <name>Simon</name> <grade>A</grade> <age>18</age> </student> </students> |
Java代碼
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 | packagenet.viralpatel.java.xmlparser; importjava.io.File; importjavax.xml.parsers.DocumentBuilder; importjavax.xml.parsers.DocumentBuilderFactory; importorg.w3c.dom.Document; importorg.w3c.dom.Element; importorg.w3c.dom.Node; importorg.w3c.dom.NodeList; publicclassXMLParser { publicvoidgetAllUserNames(String fileName) { try{ DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance(); DocumentBuilder db = dbf.newDocumentBuilder(); File file = newFile(fileName); if(file.exists()) { Document doc = db.parse(file); Element docEle = doc.getDocumentElement(); // Print root element of the document System.out.println("Root element of the document: "+ docEle.getNodeName()); NodeList studentList = docEle.getElementsByTagName("student"); // Print total student elements in document System.out .println("Total students: "+ studentList.getLength()); if(studentList != null&& studentList.getLength() > 0) { for(inti = 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); } } publicstaticvoidmain(String[] args) { XMLParser parser = newXMLParser(); parser.getAllUserNames("c:\\test.xml"); } } |
17. 把 Array 轉換成 Map
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 | importjava.util.Map; importorg.apache.commons.lang.ArrayUtils; publicclassMain { publicstaticvoidmain(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. 發送郵件
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 | importjavax.mail.*; importjavax.mail.internet.*; importjava.util.*; publicvoidpostMail( String recipients[ ], String subject, String message , String from) throwsMessagingException { booleandebug = false; //Set the host smtp address Properties props = newProperties(); props.put("mail.smtp.host", "smtp.example.com"); // create some properties and get the default Session Session session = Session.getDefaultInstance(props, null); session.setDebug(debug); // create a message Message msg = newMimeMessage(session); // set the from and to address InternetAddress addressFrom = newInternetAddress(from); msg.setFrom(addressFrom); InternetAddress[] addressTo = newInternetAddress[recipients.length]; for(inti = 0; i < recipients.length; i++) { addressTo[i] = newInternetAddress(recipients[i]); } 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); } |