西北农林科技大学信息工程学院10级Java考试不标准答案

第一题： 图形界面，输入文本地址，在TextFiled里显示内容，点击转换按钮，将大写字母转为小写字母，小写字母转为大写字母并输出在另外一个TextFiled里

 

import java.io.File;
import java.io.FileInputStream;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.swt.widgets.Label;
import org.eclipse.swt.SWT;

import org.eclipse.swt.widgets.Text;

import org.eclipse.swt.widgets.Button;

import org.eclipse.swt.events.SelectionAdapter;

import org.eclipse.swt.events.SelectionEvent;

import org.eclipse.swt.events.MouseAdapter;

import org.eclipse.swt.events.MouseEvent;

 

 

public class Task1 {

 

protected Shell shell;

private Text textPath;

private Text textRecord;

private Text textTran;

 

/**

* Launch the application.

* @param args

*/

public static void main(String[] args) {

try {

Task1 window = new Task1();

window.open();

} catch (Exception e) {

e.printStackTrace();

}

}

 

/**

* Open the window.

*/

public void open() {

Display display = Display.getDefault();

createContents();

shell.open();

shell.layout();

while (!shell.isDisposed()) {

if (!display.readAndDispatch()) {

display.sleep();

}

}

}

 

/**

* Create contents of the window.

*/

protected void createContents() {

shell = new Shell();

shell.setSize(450, 300);

shell.setText("\u6587\u672C\u7F16\u8F91\u5668");

 

Label label = new Label(shell, SWT.NONE);

label.setBounds(32, 36, 63, 13);

label.setText("\u6587\u4EF6\u8DEF\u5F84\uFF1A");

 

textPath = new Text(shell, SWT.BORDER);

textPath.setBounds(121, 36, 266, 19);

 

Button buttonRead = new Button(shell, SWT.NONE);

buttonRead.addMouseListener(new MouseAdapter() {

@Override

public void mouseUp(MouseEvent e) {

String path = textPath.getText();

 

byte bytes[]= new byte[1024];

int index=0;

try{

File file = new File(path);

if(!file.exists())

{

textRecord.setText("文本不存在");

}

else{

FileInputStream is = new FileInputStream(file);

while((index = is.read(bytes,0,1024))>0){

String str = new String(bytes,0,index);

textRecord.setText(str);

}

 

}

}

catch(Exception ee){ee.printStackTrace();}

}

});

buttonRead.addSelectionListener(new SelectionAdapter() {

@Override

public void widgetSelected(SelectionEvent e) {

}

});

buttonRead.setBounds(71, 71, 82, 23);

buttonRead.setText("\u8BFB\u5165");

 

Button buttonTrans = new Button(shell, SWT.NONE);

buttonTrans.addMouseListener(new MouseAdapter() {

@Override

public void mouseUp(MouseEvent e) {

try{

if(textRecord.getText()==null){

textTran.setText("文本域为空");

}

else{

String text=null;

byte bytes[] = new byte[1024];

char chs[]= new char[1024];

bytes = textRecord.getText().toString().getBytes();

chs = textRecord.getTextChars();

int len = textRecord.getCharCount();

int index =0;

while(index<len){

if(chs[index]<=122&&chs[index]>=97)

{

chs[index] = (char)((int)chs[index]-32);

 

}

else if(chs[index]>=65&&chs[index]<=90)

{chs[index] = (char)((int)chs[index]+32);}

index++;

 

}

textTran.setText(String.valueOf(chs));

}

}catch(Exception ee){ee.printStackTrace();}

}

});

buttonTrans.addSelectionListener(new SelectionAdapter() {

@Override

public void widgetSelected(SelectionEvent e) {

}

});

buttonTrans.setBounds(248, 71, 82, 23);

buttonTrans.setText("\u8F6C\u6362");

 

textRecord = new Text(shell, SWT.BORDER);

textRecord.setBounds(34, 100, 166, 137);

 

textTran = new Text(shell, SWT.BORDER);

textTran.setBounds(238, 100, 166, 137);

 

}

}

第二题，套接字，客户端输入一个算术式:2+3=，服务器端算出结果，返回到客户端

//客户端

import java.io.*;

import java.net.*;

public class Task2Client {

 

/**

* @param args

*/

public static void main(String[] args) {

// TODO Auto-generated method stub

try{

System.out.println("开始连接服务器");

Socket socket = new Socket("localhost", 8888);

System.out.println("已经连接服务器");

OutputStream os= socket.getOutputStream();

InputStream is = socket.getInputStream();

 

byte bytes[] = new byte[3];

//InputStreamReader isr = new InputStreamReader(System.in);

char chs[] = new char[50];

int index =0;

System.in.read(bytes);

 

os.write(bytes);

System.out.println("已经发送");

 

InputStreamReader isr = new InputStreamReader(is);

index=isr.read(chs);

System.out.println(new String(chs,0,index));

 

}catch(Exception e){e.printStackTrace();}

}

 

}

//服务器端

import java.io.*;

import java.net.*;

public class Task2Server {

 

/**

* @param args

*/

public static void main(String[] args) {

// TODO Auto-generated method stub

try{

ServerSocket ss = new ServerSocket(8888);

System.out.println("服务器开启");

Socket socket = ss.accept();

System.out.println("找到客户端");

InputStream is = socket.getInputStream();

InputStreamReader isr = new InputStreamReader(is);

OutputStream os= socket.getOutputStream();

PrintWriter pw = new PrintWriter(os);

char chs[] = new char[3];

int index =0;

float r=0;

 

while(isr.read(chs)!=-1){

int a = Integer.parseInt(String.valueOf(chs[0]));

int b = Integer.parseInt(String.valueOf(chs[2]));

 

if(chs[1]=='+')

{

r =a+b;

 

pw.write(String.valueOf(r));

pw.flush();

 

System.out.println(r);

}

else if(chs[1]=='-')

{

r =a-b;

 

pw.write(String.valueOf(r));

pw.flush();

System.out.println(r);

}

else if(chs[1]=='*')

{

r =a*b;

 

 

pw.write(String.valueOf(r));

pw.flush();

System.out.println(r);

}

else if(chs[1]=='/')

{

r =a/b;

 

pw.write(String.valueOf(r));

pw.flush();

System.out.println(chs);

 

System.out.println(r);

}

else

{

 

pw.write("Error");

 

pw.flush();

System.out.println(chs);

System.out.println("Error");

}

 

 

}

/*Socket ssocket =new Socket("localhost",8889);

OutputStream os =ssocket.getOutputStream();

OutputStreamWriter osw= new OutputStreamWriter(os);*/

 

isr.close();

is.close();

socket.close();

ss.close();

}catch(Exception e){e.printStackTrace();}

 

}

 

}

 

第三题：数据库操作，算平均分

import java.sql.*;

public class Task3 {

 

/**

* @param args

*/

public static void main(String[] args) {

// TODO Auto-generated method stub

String url ="jdbc:mysql://127.0.0.1:3306/test";

String user = "root";

String password ="";

String driver ="com.mysql.jdbc.Driver";

Connection conn =null;

PreparedStatement sql =null;

ResultSet rs = null;

int id=0;

String name=null;

float java = 0;

float j2ee =0;

float aver = 0;

try{

Class.forName(driver);

conn =DriverManager.getConnection(url,user,password);

System.out.println("连接数据库成功");

sql = conn.prepareStatement("select * from score where 1");

rs = sql.executeQuery();

while(rs.next())

{

id = rs.getInt(1);

name = rs.getString(2);

java = rs.getFloat(3);

j2ee = rs.getFloat(4);

aver = rs.getFloat(5);

System.out.println("ID:"+id+" Name:"+name+" Java:"+java+" J2EE"+j2ee+" AverageScroe:"+aver);

}

System.out.println("计算平均成绩并存入数据库");

sql = conn.prepareStatement("select * from score where 1");

rs = sql.executeQuery();

while(rs.next())

{

id = rs.getInt(1);

name = rs.getString(2);

java = rs.getFloat(3);

j2ee = rs.getFloat(4);

aver =(java+j2ee)/2;

sql = conn.prepareStatement("update score set averagescroe='"+aver+"' where id='"+id+"'");

sql.executeUpdate();

 

}

System.out.println("输出数据");

sql = conn.prepareStatement("select * from score where 1");

rs = sql.executeQuery();

while(rs.next())

{

id = rs.getInt(1);

name = rs.getString(2);

java = rs.getFloat(3);

j2ee = rs.getFloat(4);

aver = rs.getFloat(5);

System.out.println("ID:"+id+" Name:"+name+" Java:"+java+" J2EE"+j2ee+" AverageScroe:"+aver);

}

rs.close();

sql.close();

conn.close();

 

 

 

}catch(Exception e){e.printStackTrace();}

 

}

 

}