Thực hành sử dụng XML trong Java Lab 6

IT Research Department @BKAP 2015 Page 1 / 10Lab 06 XML and Databases Mục tiêu - Phân tích file XML và lấy nội dung file XML đẩy vào SQL Database - Truy nhập SQL Database lấy dữ liệu g

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Lab 06 XML and Databases Mục tiêu

- Phân tích file XML và lấy nội dung file XML đẩy vào SQL Database

- Truy nhập SQL Database lấy dữ liệu ghi ra file XML theo định dạng template-based

- Sử dụng Xquery phân tích file XML

Phần I Bài tập step by step

Bài 6.1 Phân tích nội dung file Employees.xml và đẩy nội dung file vào bảng EMPLOYEE:

 Employees.xml

 Output:

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Step 1: Tạo project java mới trong netbean

 File  New Project  Java  Java Application

 Project Name: Đặt tên Project là XMLDatabase

Step 2: Tạo File Employees.xml

 Project  New  Other  XML  XML Document

 Employees.xml

<?xml version="1.0" encoding="UTF-8"?>

<employees>

<employee id="111">

<firstname>Allen</firstname>

<lastname>Smith</lastname>

<location>Alaska</location>

<gender>M</gender>

</employee>

<employee id="112">

<firstname>John</firstname>

<lastname>Davis</lastname>

<location>Kansas</location>

<gender>M</gender>

</employee>

<employee id="113">

<firstname>Bob</firstname>

<lastname>Thomson</lastname>

<location>Kansas</location>

<gender>M</gender>

</employee>

</employees>

Step 3: Tạo bảng EMPLOYEE trong database SQL 2012

CREATE TABLE [dbo].[EMPLOYEES](

[ID] [nvarchar](50) primary key NOTNULL,

[FIRSTNAME] [nvarchar](50)NULL,

[LASTNAME] [nvarchar](50)NULL,

[LOCATION] [nvarchar](50)NULL,

[GENDER] [nvarchar](50)NULL)

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Step 4: Triển khai hàm main của ứng dụng

 XMLDatabase.java

package xmldatabase;

import java.io.File;

import java.io.IOException;

import java.sql.Connection;

import java.sql.DriverManager;

import java.sql.PreparedStatement;

import java.sql.SQLException;

import javax.xml.parsers.DocumentBuilder;

import javax.xml.parsers.DocumentBuilderFactory;

import javax.xml.parsers.ParserConfigurationException;

import org.w3c.dom.Document;

import org.w3c.dom.Element;

import org.w3c.dom.Node;

import org.w3c.dom.NodeList;

import org.xml.sax.SAXException;

/**

*

* @author DELL

*/

publicclass XMLDatabase {

/**

* @param args the command line arguments

*/

publicstaticvoid main(String[] args) throws ParserConfigurationException, SAXException, IOException,

ClassNotFoundException, InstantiationException, IllegalAccessException, SQLException {

//Parsing the XML document

File xmlFile = new File("Employees.xml");

DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();

DocumentBuilder builder = factory.newDocumentBuilder();

Document doc = builder.parse(xmlFile);

doc.getDocumentElement().normalize();

NodeList nodeList = doc.getElementsByTagName("employee");

// Connecting to database

String URL = "jdbc:sqlserver://localhost:1433;databaseName=Struts2";

String DB_DRIVER = "com.microsoft.sqlserver.jdbc.SQLServerDriver";

String user_db = "sa";

String pass_db = "Gacon1984";

Connection conn = null;

Class.forName(DB_DRIVER);

conn = DriverManager.getConnection(URL, user_db, pass_db);

String query = "INSERT INTO employees(id,firstname,lastname,location,gender) values (?,?,?,?,?)";

PreparedStatement prest = null;

prest = conn.prepareStatement(query);

// Retrieving data from XML nodes and storing in the table columns

for (int i = 0; i < nodeList.getLength(); i++) {

Node node = nodeList.item(i);

if (node.getNodeType() == Node.ELEMENT_NODE) {

Element element = (Element) node;

prest.setString(1, element.getAttribute("id"));

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prest.setString(2, element.getElementsByTagName("firstname").item(0).getTextContent());

prest.setString(3, element.getElementsByTagName("lastname").item(0).getTextContent());

prest.setString(4, element.getElementsByTagName("location").item(0).getTextContent());

prest.setString(5, element.getElementsByTagName("gender").item(0).getTextContent());

prest.execute();

}

}

conn.close();

}

}

Step 5: Build and Run ứng dụng

Bài 6.2 Lấy dữ liệu từ bảng EMPLOYEES trong SQL Database ghi ra file employees.xml từ file template-based EmployeeInfo.xml

 Input

 EmployeeInfo.xml

 Table EMPLOYEES

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 Output

Step 1: Tạo file EmployeeInfo.xml

<?xml version="1.0" encoding="UTF-8"?>

<EmployeeInfo>

<Introduction>List of employees</Introduction>

<SelectStmnt>SELECT id,firstname,lastname,location FROM employees</SelectStmnt>

<employee>

<firstName>$firstName</firstName>

<lastName>$lastName</lastName>

<location>$location</location>

</employee>

<Conclusion>End of employeelist</Conclusion>

</EmployeeInfo>

Step 2: Lấy bảng EMPLOYEE trong bài 6.1 đã làm

Step 3: Tạo JavaMain trong project bài 6.1(XMLDatabase)

 TemplateBase.java

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package xmldatabase;

import java.io.File;

import java.io.IOException;

import java.sql.Connection;

import java.sql.DriverManager;

import java.sql.ResultSet;

import java.sql.SQLException;

import java.sql.Statement;

import javax.xml.parsers.DocumentBuilder;

import javax.xml.parsers.DocumentBuilderFactory;

import javax.xml.parsers.ParserConfigurationException;

import javax.xml.transform.Transformer;

import javax.xml.transform.TransformerConfigurationException;

import javax.xml.transform.TransformerException;

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;

import org.xml.sax.SAXException;

/**

*

* @author DELL

*/

publicclass TemplateBase {

/**

* @param args the command line arguments

*/

publicstaticvoid main(String[] args) throws ParserConfigurationException, SAXException, IOException,

ClassNotFoundException, SQLException, TransformerConfigurationException, TransformerException {

//parse file EmployeeInfo and get value query

File file = new File("EmployeeInfo.xml");

DocumentBuilderFactory documentBuilderFactory = DocumentBuilderFactory.newInstance();

DocumentBuilder documentBuilder = documentBuilderFactory.newDocumentBuilder();

Document doc = documentBuilder.parse(file);

doc.getDocumentElement().normalize();

NodeList nodeList = doc.getElementsByTagName("EmployeeInfo");

Node node = nodeList.item(0);

Element eElement = (Element) node;

String query = eElement.getElementsByTagName("SelectStmnt").item(0).getTextContent();

//connect database and get data from database to resultset

String URL = "jdbc:sqlserver://localhost:1433;databaseName=Struts2";

String DB_DRIVER = "com.microsoft.sqlserver.jdbc.SQLServerDriver";

String user_db = "sa";

String pass_db = "Gacon1984";

Class.forName(DB_DRIVER);

Connection conn = DriverManager.getConnection(URL,user_db,pass_db);

Statement statement = conn.createStatement();

ResultSet rs = statement.executeQuery(query);

//write from resultset to file xml

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Document docxml = documentBuilder.newDocument();

//create root element EmployeeInfo

Element rootElement = docxml.createElement("EmployeeInfo");

docxml.appendChild(rootElement);

//create element Introduction

String itdText= eElement.getElementsByTagName("Introduction").item(0).getTextContent();

Element introduction = docxml.createElement("Introduction");

introduction.appendChild(docxml.createTextNode(itdText));

rootElement.appendChild(introduction);

while (rs.next()) {

//create element employee

Element employee = docxml.createElement("employee");

employee.setAttribute("id", rs.getString("id"));

//create element firstName,lastName,location of element employee

Element firstname = docxml.createElement("firstName");

firstname.appendChild(docxml.createTextNode(rs.getString("firstname")));

Element lastname = docxml.createElement("lastName");

lastname.appendChild(docxml.createTextNode(rs.getString("lastname")));

Element location = docxml.createElement("location");

location.appendChild(docxml.createTextNode(rs.getString("location")));

employee.appendChild(firstname);

employee.appendChild(lastname);

employee.appendChild(location);

//add employee to root element

rootElement.appendChild(employee);

}

//create element Conclusion

String cText= eElement.getElementsByTagName("Conclusion").item(0).getTextContent();

Element conclusion = docxml.createElement("Conclusion");

conclusion.appendChild(docxml.createTextNode(cText));

rootElement.appendChild(conclusion);

//write file employee.xml

TransformerFactory tfactory = TransformerFactory.newInstance();

Transformer tranformer = tfactory.newTransformer();

DOMSource source = new DOMSource(docxml);

StreamResult result = new StreamResult(new File("employees.xml"));

tranformer.transform(source, result);

}

}

Step 4: Build and Run File TemplateBase.java

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Bài 6.3

 Sử dụng Xquery in ra màn hình:

 Tất cả giá trị element firstName trong file employees.xml sinh ra trong bài 6.2

 Tất cả giá trị element firstName có location là Kansas trong file employee.xml

Step 1: Tạo java main class trong project XMLDatabase

 XMLBased.java

package xmldatabase;

import java.io.File;

import java.io.IOException;

import javax.xml.parsers.DocumentBuilder;

import javax.xml.parsers.DocumentBuilderFactory;

import javax.xml.parsers.ParserConfigurationException;

import javax.xml.xpath.XPath;

import javax.xml.xpath.XPathConstants;

import javax.xml.xpath.XPathExpressionException;

import javax.xml.xpath.XPathFactory;

import org.w3c.dom.Document;

import org.w3c.dom.NodeList;

import org.xml.sax.SAXException;

/**

*

* @author DELL

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*/

publicclass XMLBased {

/**

* @param args the command line arguments

*/

publicstaticvoid main(String[] args) throws ParserConfigurationException, SAXException, IOException,

XPathExpressionException {

//parse file employees.xml with DOM

DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();

DocumentBuilder builder = factory.newDocumentBuilder();

Document doc = builder.parse(new File("employees.xml"));

//create Xpath

XPathFactory xFactory = XPathFactory.newInstance();

XPath xPath = xFactory.newXPath();

//Xquery select all firstName

String expression1 = "/EmployeeInfo/employee/firstName";

System.out.println(expression1);

//get NodeList with expression1

NodeList nodelist1 = (NodeList) xPath.compile(expression1).evaluate(doc,XPathConstants.NODESET);

//print all firstName with expression1

for (int i = 0; i < nodelist1.getLength(); i++) {

System.out.println(nodelist1.item(i).getFirstChild().getNodeValue());

}

//Xquery select firstName with location = Kansas

String expression2 = "/EmployeeInfo/employee[location='Kansas']/firstName";

System.out.println(expression2);

//get NodeList with expression2

NodeList nodelist2 = (NodeList) xPath.compile(expression2).evaluate(doc,XPathConstants.NODESET);

//print all firstName with expression2

for (int j = 0; j < nodelist2.getLength(); j++) {

System.out.println(nodelist2.item(j).getFirstChild().getNodeValue());

}

}

}

Step 2: Build and Run File

Phần II: Bài tập tự làm

Phân tích file HangHoa.xml lấy nội dung file đưa vào table PRODUCT trong database

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