java-连接数据库（SQL server 2012）

       用Java写一个阅读器，想着要保存设置的字体、背景颜色，就连接了数据库，以下是这部分的代码：

//TestDB类的功能是连接数据库MyNote，包括对表note的查询、插入、删除等数据操作。
public class TestDB {

String result=null;

// 声明JDBC对象
Connection con = null;
Statement stmt = null;
ResultSet rs = null;

public TestDB(){
try {
// 设置连接数据库的各个参数.
@SuppressWarnings("unused")
String connectionUrl = "jdbc:sqlserver://localhost:1433;"
+ "databaseName=AdventureWorks;integratedSecurity=true;";
String url = "jdbc:sqlserver://127.0.0.1:1433;databaseName=MyNote;user=sa;password=gxu";//以sa身份连接数据库
// 建立数据库连接.
System.out.println("尝试建立数据库连接.");
Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
con = DriverManager.getConnection(url);
System.out.println("数据库连接成功!");
}
//处理和打印程序异常
catch (Exception e) {
e.printStackTrace();
}
}

public Vector<String> selectsql(String filename){
Vector<String> v=new Vector<String>();
try {
//创建SQL语句查询student表中的所有记录并返回查询结果
String SQL = "SELECT * FROM note WHERE filepath='"+filename+"';";
stmt = con.createStatement();
rs=stmt.executeQuery(SQL);
while (rs.next()) {
for(int i=0;i<10;i++)
{
result=rs.getString(i+1);
v.add(result);
}
}
/*
//遍历和打印SQL语句的查询结果
System.out.println("文件路径"+"\t\t"+"字体"+"\t"+"字形"+"\t"+"字号"+"\t"+"R"+"\t"+"G"+"\t"+"B"+"\t");
while (rs.next()) {
System.out.println(rs.getString("filepath")+"\t\t"+rs.getString("fontname")+"\t"
+rs.getString("fontstyle")+"\t"+rs.getString("fontsize")+"\t"+rs.getString("fontcolorR")+"\t"
+rs.getString("fontcolorG")+"\t"+rs.getString("fontcolorB"));
}
*/
}
//处理和打印程序异常
catch (Exception e) {
e.printStackTrace();
}
return v;
}

public void createsql(){
try {
//创建表note的SQL语句
String SQL = "CREATE TABLE note "+
"(filepath varchar(225) not NULL, "+
"fontname varchar(20), "+
"fontstyle smallint, "+
"fontsize smallint, "+
"fontcolorR smallint, "+
"fontcolorG smallint, "+
"fontcolorB smallint, "+
"backcolorR smallint, "+
"backcolorG smallint, "+
"backcolorB smallint, "+
"PRIMARY KEY (filepath))";
stmt = con.createStatement();
stmt.executeUpdate(SQL);
}
//处理和打印程序异常
catch (Exception e) {
e.printStackTrace();
}
}
public void deletesql(String filename){
try {
String SQL = "DELETE FROM note WHERE filepath='"+filename+"';";
stmt = con.createStatement();
stmt.executeUpdate(SQL);
}
//处理和打印程序异常
catch (Exception e) {
e.printStackTrace();
}

}

public void insertsql(String filepath,String fontname,int fontstyle,int fontsize,int fontcolorR,int fontcolorG,int fontcolorB,int backcolorR,int backcolorG,int backcolorB){
try {
//创建SQL语句向note表中插入一条记录
String SQL = "INSERT INTO note(filepath,fontname,fontstyle,fontsize,fontcolorR,fontcolorG,fontcolorB,backcolorR,backcolorG,backcolorB) VALUES('"+filepath+"','"+fontname+"',"+fontstyle+","+fontsize+","+fontcolorR+","+fontcolorG+","+fontcolorB+","+backcolorR+","+backcolorG+","+backcolorB+");";
stmt.executeUpdate(SQL);
}
//处理和打印程序异常
catch (Exception e) {
e.printStackTrace();
}

}
public void off(){
if (rs != null)
try {
rs.close(); //关闭查询结果集句柄
} catch (Exception e) {
}
if (stmt != null)
try {
stmt.close(); //关闭语句句柄
} catch (Exception e) {
}
if (con != null)
try {
con.close(); //关闭数据库连接
} catch (Exception e) { }
}
}