从今天开始,要在java版里玩了! welcome!jdbc or jdbc-odbc 解决方案 » 免费领取超大流量手机卡,每月29元包185G流量+100分钟通话, 中国电信官方发货 这么巧以后我也在这里玩了。DELPHHI用的差不多了,好像不能搞定太多网络的东西。所以现在开始玩java了。不过现在了java也没装。是不是应该用个jb比较好一点。 欢迎,和其他的java程序连接数据库一样,通过jdbc或者是jdbc-odbc 例子package cai;import java.awt.*;import java.awt.event.*;import java.applet.*;import javax.swing.*;import java.sql.*;import com.borland.dx.dataset.*;public class Applet1 extends Applet { private boolean isStandalone = false; JTextArea jTextArea1 = new JTextArea(); JTextField jTextField1 = new JTextField(); JButton jButton1 = new JButton(); private OpenDbBean db = new OpenDbBean(); private Connection conn = null; private ResultSet rs = null; private Statement st = null; //Get a parameter value public String getParameter(String key, String def) { return isStandalone ? System.getProperty(key, def) : (getParameter(key) != null ? getParameter(key) : def); } //Construct the applet public Applet1() { } //Initialize the applet public void init() { try { jbInit(); } catch (Exception e) { e.printStackTrace(); } } //Component initialization private void jbInit() throws Exception { jTextArea1.setText("新闻"); jTextField1.setText("请输入新闻关键字"); jTextField1.addMouseListener(new Applet1_jTextField1_mouseAdapter(this)); jButton1.setText("确定"); jButton1.addMouseListener(new Applet1_jButton1_mouseAdapter(this)); this.add(jTextArea1, null); this.add(jTextField1, null); this.add(jButton1, null); } //Get Applet information public String getAppletInfo() { return "Applet Information"; } //Get parameter info public String[][] getParameterInfo() { return null; } void jButton1_mouseClicked(MouseEvent e) { try { conn = db.getConnection(); st = conn.createStatement(); String sql = "select * from news where n_title like '%" + jTextField1.getText() + "%'"; System.out.println(sql); rs = st.executeQuery(sql); Graphics g = this.getGraphics(); int i = 10; g.drawString("编号", 40, 40); g.drawString("名称", 80, 40); g.drawString("内容", 160, 40); while (rs.next()) { g.drawString(rs.getString("n_id"), 40, 60 + i); g.drawString(new String(rs.getString("n_title").getBytes("ISO8859_1"), "GBK"), 80, 60 + i); g.drawString(new String(rs.getString("n_content").getBytes("ISO8859_1"), "GBK"), 160, 60 + i); i += 20; } } catch (Exception ex) { System.out.println(ex.getMessage()); } } void jTextField1_mouseClicked(MouseEvent e) { jTextField1.setText(""); }}class Applet1_jButton1_mouseAdapter extends java.awt.event.MouseAdapter { Applet1 adaptee; Applet1_jButton1_mouseAdapter(Applet1 adaptee) { this.adaptee = adaptee; } public void mouseClicked(MouseEvent e) { adaptee.jButton1_mouseClicked(e); }}class Applet1_jTextField1_mouseAdapter extends java.awt.event.MouseAdapter { Applet1 adaptee; Applet1_jTextField1_mouseAdapter(Applet1 adaptee) { this.adaptee = adaptee; } public void mouseClicked(MouseEvent e) { adaptee.jTextField1_mouseClicked(e); }} 恩,用applet直接连,我也会一点点了!但是总觉得这样的话,系统的性能上有所不足!试想,如果同时有100000个客户端都连接的话,那么数据库服务器的负担有多重?而且以后来说,软件的收费主要变成了license授权收费,多一个连接就需要一个的钱所以我像能不能做个中间层阿?当然如果用web service的话,就简单了,但是咱没钱啊!怎么办? 呵呵,我也是,在Delphi版块里逛了5个月,来这里了,呵呵我的QQ:175322659志同道合者不妨做个朋友,一起学习JAVA。 正确,在很多用户访问系统的时候,建议还是采用J2EE架构比较好你可以使用中间层,在要求不是很严格的情况下,应用服务器可以选择免费的Tomcat PS:再说一句,10w个客户同时访问,放在那里的系统都估计要崩溃的一般的J2EE系统,同时可以满足几百上千用户访问而不会性能下降的,就算很不错的 偶以前在PB版里,现在也转学JAVA了,偶前来报道! 大家看看这个计算器的代码写的合理吗 十六进制整型赋值出错 欢迎讨论-->java多线程(优先级,依赖性,动态等结合) 有几个简单的问题,请教下大家(高分,但是简单!!) 新手又有个问题了 在对话框中如何获得正在运行的Applet实例 请问关于路径设置的问题 数值转换的问题 一个百思不得其解的问题(数据库) 各位大神帮忙看个java 多线程的程序 在线等--问题求解 java应用在什么方面?
DELPHHI用的差不多了,
好像不能搞定太多网络的东西。
所以现在开始玩java了。不过现在了java也没装。是不是应该用个jb比较好一点。
package cai;import java.awt.*;
import java.awt.event.*;
import java.applet.*;
import javax.swing.*;
import java.sql.*;
import com.borland.dx.dataset.*;public class Applet1
extends Applet {
private boolean isStandalone = false;
JTextArea jTextArea1 = new JTextArea();
JTextField jTextField1 = new JTextField();
JButton jButton1 = new JButton();
private OpenDbBean db = new OpenDbBean();
private Connection conn = null;
private ResultSet rs = null;
private Statement st = null; //Get a parameter value
public String getParameter(String key, String def) {
return isStandalone ? System.getProperty(key, def) :
(getParameter(key) != null ? getParameter(key) : def);
} //Construct the applet
public Applet1() {
} //Initialize the applet
public void init() {
try {
jbInit();
}
catch (Exception e) {
e.printStackTrace();
}
} //Component initialization
private void jbInit() throws Exception {
jTextArea1.setText("新闻");
jTextField1.setText("请输入新闻关键字");
jTextField1.addMouseListener(new Applet1_jTextField1_mouseAdapter(this));
jButton1.setText("确定");
jButton1.addMouseListener(new Applet1_jButton1_mouseAdapter(this));
this.add(jTextArea1, null);
this.add(jTextField1, null);
this.add(jButton1, null);
} //Get Applet information
public String getAppletInfo() {
return "Applet Information";
} //Get parameter info
public String[][] getParameterInfo() {
return null;
} void jButton1_mouseClicked(MouseEvent e) {
try {
conn = db.getConnection();
st = conn.createStatement();
String sql = "select * from news where n_title like '%" +
jTextField1.getText() + "%'";
System.out.println(sql);
rs = st.executeQuery(sql);
Graphics g = this.getGraphics();
int i = 10;
g.drawString("编号", 40, 40);
g.drawString("名称", 80, 40);
g.drawString("内容", 160, 40);
while (rs.next()) {
g.drawString(rs.getString("n_id"), 40, 60 + i);
g.drawString(new String(rs.getString("n_title").getBytes("ISO8859_1"), "GBK"), 80, 60 + i);
g.drawString(new String(rs.getString("n_content").getBytes("ISO8859_1"), "GBK"), 160, 60 + i);
i += 20;
} }
catch (Exception ex) {
System.out.println(ex.getMessage());
}
} void jTextField1_mouseClicked(MouseEvent e) {
jTextField1.setText("");
}
}class Applet1_jButton1_mouseAdapter
extends java.awt.event.MouseAdapter {
Applet1 adaptee; Applet1_jButton1_mouseAdapter(Applet1 adaptee) {
this.adaptee = adaptee;
} public void mouseClicked(MouseEvent e) {
adaptee.jButton1_mouseClicked(e);
}
}class Applet1_jTextField1_mouseAdapter
extends java.awt.event.MouseAdapter {
Applet1 adaptee; Applet1_jTextField1_mouseAdapter(Applet1 adaptee) {
this.adaptee = adaptee;
} public void mouseClicked(MouseEvent e) {
adaptee.jTextField1_mouseClicked(e);
}
}