XML—DOM解析案例
互联网
17-2-24
【题目】：基于XML文件实现一个简易的控制台程序，可以查看学生成绩，添加学生，删除学生等。
xml文件保存在src/com/dom/exercise文件夹下，它的格式如下：
<?xml version="1.0" encoding="utf-8" standalone="no"?><students> <student sid="001"> <name>小明</name> <course> <java>90</java> <oracle>90</oracle> <vb>93</vb> </course> </student> <student sid="002"> <name>小李</name> <course> <java>78</java> <oracle>86</oracle> <vb>98</vb> </course> </student> <student sid="003"> <name>小王</name> <course> <java>89</java> <oracle>83</oracle> <vb>95</vb> </course> </student></students>
这个可以说是最简单的程序了，稍微复杂的一点是它要基于XML文件来实现，所以这里肯定要使用DOM解析，SAX不能用是因为SAX解析只能读取XML文件而不能更新。
1.首先编写StudentBean，如下：
package com.dom.exercise;public class Student { private String id = null; private String name = null; private int score_java; private int score_oracle; private int score_vb; public Student() { } public Student(String id, String name, int score_java, int score_oracle, int score_vb) { super(); this.id = id; this.name = name; this.score_java = score_java; this.score_oracle = score_oracle; this.score_vb = score_vb; } public String getId() { return id; } public void setId(String id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public int getScore_java() { return score_java; } public void setScore_java(int score_java) { this.score_java = score_java; } public int getScore_oracle() { return score_oracle; } public void setScore_oracle(int score_oracle) { this.score_oracle = score_oracle; } public int getScore_vb() { return score_vb; } public void setScore_vb(int score_vb) { this.score_vb = score_vb; } }2.编写最关键的StudentService类，它对XML文档进行各种操作
import java.util.ArrayList; import javax.xml.parsers.DocumentBuilder; import javax.xml.parsers.DocumentBuilderFactory; import javax.xml.transform.Transformer; import javax.xml.transform.TransformerFactory; import javax.xml.transform.dom.DOMSource; import javax.xml.transform.stream.StreamResult; import org.w3c.dom.Document; import org.w3c.dom.Element; import org.w3c.dom.Node; import org.w3c.dom.NodeList; public class StudentService { private static Document document = null; private static String path = "src/com/dom/exercise/student.xml"; static{ try{ DocumentBuilderFactory documentBuilderFactory = DocumentBuilderFactory.newInstance(); DocumentBuilder documentBuilder = documentBuilderFactory.newDocumentBuilder(); document = documentBuilder.parse(path); }catch(Exception e){ System.out.println("初始化失败..."); e.printStackTrace(); } } /** * 获取所有学生信息 * @return */ public static ArrayList<Student> readAll(){ ArrayList<Student> array = new ArrayList<Student>(); NodeList students = document.getElementsByTagName("student"); for (int i = 0; i < students.getLength(); i++) { Element node_student = (Element)students.item(i); String id = node_student.getAttribute("sid"); Node node_name = node_student.getElementsByTagName("name").item(0); String name = node_name.getTextContent(); Element node_course = (Element)node_student.getElementsByTagName("course").item(0); Node course_java = node_course.getElementsByTagName("java").item(0); Node course_oracle = node_course.getElementsByTagName("oracle").item(0); Node course_vb = node_course.getElementsByTagName("vb").item(0); int score_java = Integer.parseInt(course_java.getTextContent()); int score_oracle = Integer.parseInt(course_oracle.getTextContent()); int score_vb = Integer.parseInt(course_vb.getTextContent()); Student student = new Student(id, name, score_java, score_oracle, score_vb); array.add(student); } return array; } /** * 根据ID获取一个学生的信息 * @param sid * @return */ public static Student getStudentById(String sid){ NodeList students = document.getElementsByTagName("student"); for (int i = 0; i < students.getLength(); i++) { Element node_student = (Element)students.item(i); String id = node_student.getAttribute("sid"); if(!id.equals(sid)){ continue; } Node node_name = node_student.getElementsByTagName("name").item(0); String name = node_name.getTextContent(); Element node_course = (Element)node_student.getElementsByTagName("course").item(0); Node course_java = node_course.getElementsByTagName("java").item(0); Node course_oracle = node_course.getElementsByTagName("oracle").item(0); Node course_vb = node_course.getElementsByTagName("vb").item(0); int score_java = Integer.parseInt(course_java.getTextContent()); int score_oracle = Integer.parseInt(course_oracle.getTextContent()); int score_vb = Integer.parseInt(course_vb.getTextContent()); Student student = new Student(id, name, score_java, score_oracle, score_vb); return student; } return null; } /** * 添加学生 * @param student */ public static void addStudent(Student student){ Element stu = document.createElement("student"); stu.setAttribute("sid", student.getId()); Element name = document.createElement("name"); name.setTextContent(student.getName()); Element course = document.createElement("course"); Element score_java = document.createElement("java"); Element score_oracle = document.createElement("oracle"); Element score_vb = document.createElement("vb"); score_java.setTextContent(String.valueOf(student.getScore_java())); score_oracle.setTextContent(String.valueOf(student.getScore_oracle())); score_vb.setTextContent(String.valueOf(student.getScore_vb())); course.appendChild(score_java); course.appendChild(score_oracle); course.appendChild(score_vb); stu.appendChild(name); stu.appendChild(course); document.getDocumentElement().appendChild(stu); update(document, path); } /** * 根据ID删除一个学生 * @param sid */ public static void deleteStudentById(String sid){ NodeList students = document.getElementsByTagName("student"); for (int i = 0; i < students.getLength(); i++) { Element student = (Element)students.item(i); if(student.getAttribute("sid").equals(sid)){ student.getParentNode().removeChild(student); } } update(document,path); } /** * 更新到文件 * @param document * @param path */ public static void update(Document document,String path){ try{ TransformerFactory transformerFactory = TransformerFactory.newInstance(); Transformer transformer = transformerFactory.newTransformer(); transformer.transform(new DOMSource(document), new StreamResult(new File(path))); }catch(Exception e){ e.printStackTrace(); } } }3.编写主测试程序 实现简易界面：
package com.dom.exercise; import java.util.ArrayList; import java.util.Scanner; public class Main { public static void main(String[] args) { Scanner scanner = new Scanner(System.in); boolean flag = true; while(flag){ // 显示操作界面 System.console(); System.out.println("*********************操作界面*********************"); System.out.println("\t\t1.查询所有学生的成绩"); System.out.println("\t\t2.按照ID查询学生成绩 "); System.out.println("\t\t3.添加一个学生"); System.out.println("\t\t4.按照ID删除一个学生"); System.out.println("\t\t0.退出系统"); System.out.println("************************************************"); // 获取用户的操作 String operate = scanner.next(); if ("1".equals(operate)) { ArrayList<Student> students = StudentService.readAll(); System.out.println("所有的学生信息如下："); System.out.println("Name\tID\tJava\tOracle\tVB"); for (Student student : students) { System.out.println(student.getName() + "\t" + student.getId() + "\t" + student.getScore_java() + "\t" + student.getScore_oracle() + "\t" + student.getScore_vb()); } }else if("2".equals(operate)){ System.out.println("请输入要查询的学生ID："); String sid = scanner.next(); Student student = StudentService.getStudentById(sid); System.out.println("学号为"+sid+"的学生的信息如下："); System.out.println("Name\tID\tJava\tOracle\tVB"); System.out.println(student.getName() + "\t" + student.getId() + "\t" + student.getScore_java() + "\t" + student.getScore_oracle() + "\t" + student.getScore_vb()); }else if("3".equals(operate)){ System.out.println("请输入要添加的学生ID："); String sid = scanner.next(); System.out.println("请输入要添加的学生姓名："); String name = scanner.next(); System.out.println("请输入要添加的学生Java成绩："); int score_java = Integer.parseInt(scanner.next()); System.out.println("请输入要添加的学生Oracle成绩："); int score_oracle = Integer.parseInt(scanner.next()); System.out.println("请输入要添加的学生VB成绩："); int score_vb = Integer.parseInt(scanner.next()); Student student = new Student(sid, name, score_java, score_oracle, score_vb); StudentService.addStudent(student); System.out.println("添加成功！"); }else if("4".equals(operate)){ System.out.println("请输入要删除的学生的ID："); String sid = scanner.next(); StudentService.deleteStudentById(sid); System.out.println("删除成功！"); } System.out.println("是否继续？(Y/N)"); flag = scanner.next().trim().toLowerCase().equals("y")?true:false; } scanner.close(); } }4.运行结果 
问题的关键仍是DOM解析XML，对XML进行crud操作。
【题目】：基于XML文件实现一个简易的控制台程序，可以查看学生成绩，添加学生，删除学生等。
xml文件保存在src/com/dom/exercise文件夹下，它的格式如下：
<?xml version="1.0" encoding="utf-8" standalone="no"?><students> <student sid="001"> <name>小明</name> <course> <java>90</java> <oracle>90</oracle> <vb>93</vb> </course> </student> <student sid="002"> <name>小李</name> <course> <java>78</java> <oracle>86</oracle> <vb>98</vb> </course> </student> <student sid="003"> <name>小王</name> <course> <java>89</java> <oracle>83</oracle> <vb>95</vb> </course> </student></students>
这个可以说是最简单的程序了，稍微复杂的一点是它要基于XML文件来实现，所以这里肯定要使用DOM解析，SAX不能用是因为SAX解析只能读取XML文件而不能更新。
1.首先编写StudentBean，如下：
package com.dom.exercise;public class Student { private String id = null; private String name = null; private int score_java; private int score_oracle; private int score_vb; public Student() { } public Student(String id, String name, int score_java, int score_oracle, int score_vb) { super(); this.id = id; this.name = name; this.score_java = score_java; this.score_oracle = score_oracle; this.score_vb = score_vb; } public String getId() { return id; } public void setId(String id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public int getScore_java() { return score_java; } public void setScore_java(int score_java) { this.score_java = score_java; } public int getScore_oracle() { return score_oracle; } public void setScore_oracle(int score_oracle) { this.score_oracle = score_oracle; } public int getScore_vb() { return score_vb; } public void setScore_vb(int score_vb) { this.score_vb = score_vb; } }2.编写最关键的StudentService类，它对XML文档进行各种操作
import java.util.ArrayList; import javax.xml.parsers.DocumentBuilder; import javax.xml.parsers.DocumentBuilderFactory; import javax.xml.transform.Transformer; import javax.xml.transform.TransformerFactory; import javax.xml.transform.dom.DOMSource; import javax.xml.transform.stream.StreamResult; import org.w3c.dom.Document; import org.w3c.dom.Element; import org.w3c.dom.Node; import org.w3c.dom.NodeList; public class StudentService { private static Document document = null; private static String path = "src/com/dom/exercise/student.xml"; static{ try{ DocumentBuilderFactory documentBuilderFactory = DocumentBuilderFactory.newInstance(); DocumentBuilder documentBuilder = documentBuilderFactory.newDocumentBuilder(); document = documentBuilder.parse(path); }catch(Exception e){ System.out.println("初始化失败..."); e.printStackTrace(); } } /** * 获取所有学生信息 * @return */ public static ArrayList<Student> readAll(){ ArrayList<Student> array = new ArrayList<Student>(); NodeList students = document.getElementsByTagName("student"); for (int i = 0; i < students.getLength(); i++) { Element node_student = (Element)students.item(i); String id = node_student.getAttribute("sid"); Node node_name = node_student.getElementsByTagName("name").item(0); String name = node_name.getTextContent(); Element node_course = (Element)node_student.getElementsByTagName("course").item(0); Node course_java = node_course.getElementsByTagName("java").item(0); Node course_oracle = node_course.getElementsByTagName("oracle").item(0); Node course_vb = node_course.getElementsByTagName("vb").item(0); int score_java = Integer.parseInt(course_java.getTextContent()); int score_oracle = Integer.parseInt(course_oracle.getTextContent()); int score_vb = Integer.parseInt(course_vb.getTextContent()); Student student = new Student(id, name, score_java, score_oracle, score_vb); array.add(student); } return array; } /** * 根据ID获取一个学生的信息 * @param sid * @return */ public static Student getStudentById(String sid){ NodeList students = document.getElementsByTagName("student"); for (int i = 0; i < students.getLength(); i++) { Element node_student = (Element)students.item(i); String id = node_student.getAttribute("sid"); if(!id.equals(sid)){ continue; } Node node_name = node_student.getElementsByTagName("name").item(0); String name = node_name.getTextContent(); Element node_course = (Element)node_student.getElementsByTagName("course").item(0); Node course_java = node_course.getElementsByTagName("java").item(0); Node course_oracle = node_course.getElementsByTagName("oracle").item(0); Node course_vb = node_course.getElementsByTagName("vb").item(0); int score_java = Integer.parseInt(course_java.getTextContent()); int score_oracle = Integer.parseInt(course_oracle.getTextContent()); int score_vb = Integer.parseInt(course_vb.getTextContent()); Student student = new Student(id, name, score_java, score_oracle, score_vb); return student; } return null; } /** * 添加学生 * @param student */ public static void addStudent(Student student){ Element stu = document.createElement("student"); stu.setAttribute("sid", student.getId()); Element name = document.createElement("name"); name.setTextContent(student.getName()); Element course = document.createElement("course"); Element score_java = document.createElement("java"); Element score_oracle = document.createElement("oracle"); Element score_vb = document.createElement("vb"); score_java.setTextContent(String.valueOf(student.getScore_java())); score_oracle.setTextContent(String.valueOf(student.getScore_oracle())); score_vb.setTextContent(String.valueOf(student.getScore_vb())); course.appendChild(score_java); course.appendChild(score_oracle); course.appendChild(score_vb); stu.appendChild(name); stu.appendChild(course); document.getDocumentElement().appendChild(stu); update(document, path); } /** * 根据ID删除一个学生 * @param sid */ public static void deleteStudentById(String sid){ NodeList students = document.getElementsByTagName("student"); for (int i = 0; i < students.getLength(); i++) { Element student = (Element)students.item(i); if(student.getAttribute("sid").equals(sid)){ student.getParentNode().removeChild(student); } } update(document,path); } /** * 更新到文件 * @param document * @param path */ public static void update(Document document,String path){ try{ TransformerFactory transformerFactory = TransformerFactory.newInstance(); Transformer transformer = transformerFactory.newTransformer(); transformer.transform(new DOMSource(document), new StreamResult(new File(path))); }catch(Exception e){ e.printStackTrace(); } } }3.编写主测试程序 实现简易界面：
package com.dom.exercise;import java.util.ArrayList;import java.util.Scanner;public class Main { public static void main(String[] args) { Scanner scanner = new Scanner(System.in); boolean flag = true; while(flag){ // 显示操作界面 System.console(); System.out.println("*********************操作界面*********************"); System.out.println("\t\t1.查询所有学生的成绩"); System.out.println("\t\t2.按照ID查询学生成绩 "); System.out.println("\t\t3.添加一个学生"); System.out.println("\t\t4.按照ID删除一个学生"); System.out.println("\t\t0.退出系统"); System.out.println("************************************************"); // 获取用户的操作 String operate = scanner.next(); if ("1".equals(operate)) { ArrayList<Student> students = StudentService.readAll(); System.out.println("所有的学生信息如下："); System.out.println("Name\tID\tJava\tOracle\tVB"); for (Student student : students) { System.out.println(student.getName() + "\t" + student.getId() + "\t" + student.getScore_java() + "\t" + student.getScore_oracle() + "\t" + student.getScore_vb()); } }else if("2".equals(operate)){ System.out.println("请输入要查询的学生ID："); String sid = scanner.next(); Student student = StudentService.getStudentById(sid); System.out.println("学号为"+sid+"的学生的信息如下："); System.out.println("Name\tID\tJava\tOracle\tVB"); System.out.println(student.getName() + "\t" + student.getId() + "\t" + student.getScore_java() + "\t" + student.getScore_oracle() + "\t" + student.getScore_vb()); }else if("3".equals(operate)){ System.out.println("请输入要添加的学生ID："); String sid = scanner.next(); System.out.println("请输入要添加的学生姓名："); String name = scanner.next(); System.out.println("请输入要添加的学生Java成绩："); int score_java = Integer.parseInt(scanner.next()); System.out.println("请输入要添加的学生Oracle成绩："); int score_oracle = Integer.parseInt(scanner.next()); System.out.println("请输入要添加的学生VB成绩："); int score_vb = Integer.parseInt(scanner.next()); Student student = new Student(sid, name, score_java, score_oracle, score_vb); StudentService.addStudent(student); System.out.println("添加成功！"); }else if("4".equals(operate)){ System.out.println("请输入要删除的学生的ID："); String sid = scanner.next(); StudentService.deleteStudentById(sid); System.out.println("删除成功！"); } System.out.println("是否继续？(Y/N)"); flag = scanner.next().trim().toLowerCase().equals("y")?true:false; } scanner.close(); } }4.运行结果
问题的关键仍是DOM解析XML，对XML进行crud操作。
以上就是XML—DOM解析案例的内容，更多相关内容请关注PHP中文网（www.php.cn）！
免责声明：
1.资讯内容不构成投资建议，投资者应独立决策并自行承担风险
2.本文版权归属原作所有，仅代表作者本人观点，不代表本站的观点或立场
1.资讯内容不构成投资建议，投资者应独立决策并自行承担风险
2.本文版权归属原作所有，仅代表作者本人观点，不代表本站的观点或立场
相关资讯
扫码关注公众号
技术文章 / 下载软件
趣味内容 / 专业带飞
