J2EE全套笔试面试题（4文档终极汇总版）(7)

}

public boolean executeUpdate(String sql) { try {

conn.executeUpdate(sql); return true; }

catch (SQLException e) {

e.printStackTrace(); return false; } }

public ResultSet executeQuery(String sql) {

rs=null; try {

rs=conn.executeQuery(sql); }

catch (SQLException e) {

e.printStackTrace(); }

return rs; }

public void close() { try {

conn.close(); c.close(); }

catch (Exception e) {

e.printStackTrace(); } }

public static void main(String[] args) {

ResultSet rs;

jdbc conn = new jdbc();

rs=conn.executeQuery(\* from test\

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try{

while (rs.next()) {

System.out.println(rs.getString(\ System.out.println(rs.getString(\ }

}catch(Exception e) {

e.printStackTrace(); } } }

143、ORACLE大数据量下的分页解决方法。一般用截取ID方法，还有是三层嵌套方法。 答:一种分页方法 <% int i=1;

int numPages=14;

String pages = request.getParameter(\; int currentPage = 1;

currentPage=(pages==null)?(1):{Integer.parseInt(pages)} sql = \count(*) from tables\ ResultSet rs = DBLink.executeQuery(sql) ; while(rs.next()) i = rs.getInt(1) ; int intPageCount=1;

intPageCount=(i%numPages==0)?(i/numPages):(i/numPages+1); int nextPage ; int upPage;

nextPage = currentPage+1;

if (nextPage>=intPageCount) nextPage=intPageCount; upPage = currentPage-1; if (upPage<=1) upPage=1; rs.close();

sql=\* from tables\ rs=DBLink.executeQuery(sql); i=0;

while((i //输出内容 //输出翻页连接

合计:<%=currentPage%>/<%=intPageCount%>

href=\上一页 <%

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for(int j=1;j<=intPageCount;j++){ if(currentPage!=j){ %>

\最后页

144、用jdom解析xml文件时如何解决中文问题?如何解析? 答:看如下代码,用编码方式加以解决 package test; import java.io.*; public class DOMTest {

private String inFile = \ private String outFile = \ public static void main(String args[]) {

new DOMTest(); }

public DOMTest() { try {

javax.xml.parsers.DocumentBuilder builder =

javax.xml.parsers.DocumentBuilderFactory.newInstance().newDocumentBuilder(); org.w3c.dom.Document doc = builder.newDocument(); org.w3c.dom.Element root = doc.createElement(\老师\ org.w3c.dom.Element wang = doc.createElement(\王\ org.w3c.dom.Element liu = doc.createElement(\刘\ wang.appendChild(doc.createTextNode(\我是王老师\ root.appendChild(wang); doc.appendChild(root);

javax.xml.transform.Transformer transformer =

javax.xml.transform.TransformerFactory.newInstance().newTransformer(); transformer.setOutputProperty(javax.xml.transform.OutputKeys.ENCODING,

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\

transformer.setOutputProperty(javax.xml.transform.OutputKeys.INDENT, \es\

transformer.transform(new javax.xml.transform.dom.DOMSource(doc), new

javax.xml.transform.stream.StreamResult(outFile)); }

catch (Exception e) {

System.out.println (e.getMessage()); } } }

145、编程用JAVA解析XML的方式. 答:用SAX方式解析XML，XML文件如下：

王小明 信息学院 6258113

男,1955年生,博士，95年调入海南大学

事件回调类SAXHandler.java import java.io.*;

import java.util.Hashtable; import org.xml.sax.*;

public class SAXHandler extends HandlerBase {

private Hashtable table = new Hashtable(); private String currentElement = null; private String currentValue = null; public void setTable(Hashtable table) {

this.table = table; }

public Hashtable getTable() {

return table; }

public void startElement(String tag, AttributeList attrs) throws SAXException

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{

currentElement = tag; }

public void characters(char[] ch, int start, int length) throws SAXException {

currentValue = new String(ch, start, length); }

public void endElement(String name) throws SAXException {

if (currentElement.equals(name))

table.put(currentElement, currentValue); } }

JSP内容显示源码,SaxXml.jsp:

<%@ page errorPage=\

contentType=\%> <%@ page import=\%>

<%@ page import=\%> <%@ page import=\%> <%@ page import=\%>

<%@ page import=\%> <%@ page import=\%> <%@ page import=\%> <%

File file = new File(\ FileReader reader = new FileReader(file); Parser parser;

SAXParserFactory spf = SAXParserFactory.newInstance(); SAXParser sp = spf.newSAXParser(); SAXHandler handler = new SAXHandler(); sp.parse(new InputSource(reader), handler); Hashtable hashTable = handler.getTable();

out.println(\BORDER=2>教师信息表\ out.println(\姓名\+ \+

(String)hashTable.get(new String(\+ \ out.println(\学院\+ \+

(String)hashTable.get(new String(\ out.println(\电话\+ \+

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