tools.java

在线考试系统

package jinghua;

import java.io.*;
import java.sql.*;
import java.text.SimpleDateFormat;
import java.util.Date;
import javax.servlet.jsp.JspWriter;

public class Tools
{

    public Tools()
    {
    }

    public static void showalert(String msg, JspWriter out)
    {
        try
        {
            out.print(String.valueOf(String.valueOf((new StringBuffer("<SCRIPT LANGUAGE=\"javascript\"\n>    alert(\"")).append(msg).append("\");\n").append("</SCRIPT>\n"))));
        }
        catch(Exception e)
        {
            System.out.println(e.toString());
        }
    }

    public static void goback(JspWriter out)
    {
        try
        {
            out.print("<SCRIPT LANGUAGE=\"javascript\"\n>    history.go(-1);\n</SCRIPT>\n");
        }
        catch(Exception e)
        {
            System.out.println(e.toString());
        }
    }

    public static void showJS(String msg, JspWriter out)
    {
        try
        {
            out.print(String.valueOf(String.valueOf((new StringBuffer("<SCRIPT LANGUAGE=\"javascript\"\n>")).append(msg).append(";\n").append("</SCRIPT>\n"))));
        }
        catch(Exception e)
        {
            System.out.println(e.toString());
        }
    }

    public static void debugmsg(String msg, JspWriter out)
    {
        try
        {
            out.print(msg);
        }
        catch(Exception e)
        {
            System.out.println(e.toString());
        }
    }

    public static void showOption(String sql, Connection con, JspWriter out)
    {
        Statement stmt = null;
        ResultSet rs = null;
        try
        {
            stmt = con.createStatement();
            for(rs = stmt.executeQuery(sql); rs.next(); out.print(String.valueOf(String.valueOf((new StringBuffer("<OPTION value=")).append(rs.getInt("ID")).append(">").append(rs.getString("Name")).append("</OPTION>")))));
            rs.close();
            stmt.close();
        }
        catch(SQLException se)
        {
            try
            {
                out.print(se);
            }
            catch(Exception exception) { }
        }
        catch(Exception se)
        {
            try
            {
                out.print(se);
            }
            catch(Exception exception1) { }
        }
    }

    public static void showGradeOption(Connection con, JspWriter out)
    {
        Statement stmt = null;
        ResultSet rs = null;
        String sql = "select * from grade order by id";
        try
        {
            stmt = con.createStatement();
            for(rs = stmt.executeQuery(sql); rs.next(); out.print(String.valueOf(String.valueOf((new StringBuffer("<OPTION value=\"")).append(rs.getString("note")).append("\">").append(rs.getString("Name")).append("</OPTION>")))));
            rs.close();
            stmt.close();
        }
        catch(SQLException se)
        {
            try
            {
                out.print(se);
            }
            catch(Exception exception) { }
        }
        catch(Exception se)
        {
            try
            {
                out.print(se);
            }
            catch(Exception exception1) { }
        }
    }

    public static void showGradeSubjectOption(Connection con, String gradenote, JspWriter out)
    {
        Statement stmt = null;
        ResultSet rs = null;
        String sql = String.valueOf(String.valueOf((new StringBuffer("SELECT   `subject`.`Name`,  `subject`.`ID` FROM   `subject` WHERE  (`subject`.`gradenote` = '")).append(gradenote).append("')")));
        try
        {
            stmt = con.createStatement();
            for(rs = stmt.executeQuery(sql); rs.next(); out.print(String.valueOf(String.valueOf((new StringBuffer("<OPTION value=\"")).append(rs.getString("ID")).append("\">").append(rs.getString("Name")).append("</OPTION>")))));
            rs.close();
            stmt.close();
        }
        catch(SQLException se)
        {
            try
            {
                out.print(se);
            }
            catch(Exception exception) { }
        }
        catch(Exception se)
        {
            try
            {
                out.print(se);
            }
            catch(Exception exception1) { }
        }
    }

    public static String codestring(String s)
    {
        String str = s;
        String s2;
        try
        {
            byte b[] = str.getBytes("ISO-8859-1");
            str = new String(b);
            String s1 = str;
            return s1;
        }
        catch(Exception e)
        {
            s2 = str;
        }
        return s2;
    }

    public static String toHtml(String str)
    {
        String html = str;
        html = Replace(html, "&", "&amp;");
        html = Replace(html, "<", "&lt;");
        html = Replace(html, ">", "&gt;");
        html = Replace(html, "\r\n", "\n");
        html = Replace(html, "\n", "<br>\n");
        html = Replace(html, "\t", "    ");
        html = Replace(html, "  ", "  ");
        return html;
    }

    public static String toSql(String sqlstr)
    {
        String strsql = sqlstr;
        strsql = Replace(strsql, "'", "''");
        return strsql;
    }

    public static String readFile(String filename)
    {
        String httpText = null;
        try
        {
            File file = new File(filename);
            FileInputStream fis = new FileInputStream(file);
            byte webxml[] = new byte[fis.available()];
            fis.read(webxml);
            httpText = new String(webxml);
        }
        catch(FileNotFoundException e2)
        {
            e2.printStackTrace();
        }
        catch(IOException e)
        {
            e.printStackTrace();
        }
        System.out.print(httpText);
        return httpText;
    }

    public static String Replace(String source, String oldString, String newString)
    {
        StringBuffer output = new StringBuffer();
        int lengthOfSource = source.length();
        int lengthOfOld = oldString.length();
        int posStart;
        int pos;
        for(posStart = 0; (pos = source.indexOf(oldString, posStart)) >= 0; posStart = pos + lengthOfOld)
        {
            output.append(source.substring(posStart, pos));
            output.append(newString);
        }

        if(posStart < lengthOfSource)
            output.append(source.substring(posStart));
        return output.toString();
    }

    public static String ReplaceFirst(String source, String oldString, String newString)
    {
        StringBuffer output = new StringBuffer();
        int lengthOfSource = source.length();
        int lengthOfOld = oldString.length();
        int posStart = 0;
        int pos;
        if((pos = source.indexOf(oldString, posStart)) >= 0)
        {
            output.append(source.substring(posStart, pos));
            output.append(newString);
            posStart = pos + lengthOfOld;
        }
        if(posStart < lengthOfSource)
            output.append(source.substring(posStart));
        return output.toString();
    }

    public static String selgrade_sub(Connection con)
    {
        int i = 0;
        StringBuffer sb = new StringBuffer("");
        String sql = "select id,name,gradenote from subject order by gradenote,id";
        try
        {
            PreparedStatement pstmt = con.prepareStatement(sql);
            ResultSet rs = pstmt.executeQuery();
            sb.append("<script language =\"JavaScript\">\n");
            sb.append("var gscount;\n");
            sb.append("gscount=0;\n");
            sb.append("grade_sub=new Array();\n");
            while(rs.next()) 
            {
                sb.append(String.valueOf(String.valueOf((new StringBuffer("grade_sub[")).append(i).append("]=new Array(\"").append(rs.getString("gradenote")).append("\",\"").append(rs.getInt("id")).append("\",\"").append(rs.getString("name")).append("\")\n"))));
                i++;
            }
            sb.append(String.valueOf(String.valueOf((new StringBuffer("gscount=")).append(i).append("\n"))));
            sb.append("function changegs(locationid)\n");
            sb.append("{\n");
            sb.append("document.myform.selsubject.length =1;\n");
            sb.append("var locationid=locationid;\n");
            sb.append("var i;\n");
            sb.append("for (i=0;i < gscount; i++)\n");
            sb.append("{\n");
            sb.append("if (grade_sub[i][0] == locationid)\n");
            sb.append("{\n");
            sb.append("document.myform.selsubject.options[document.myform.selsubject.length] = new Option(grade_sub[i][2], grade_sub[i][1]);\n");
            sb.append("}\n}\n}\n");
            sb.append("</script>\n");
        }
        catch(SQLException se)
        {
            System.out.print(se.toString());
        }
        return sb.toString();
    }

    public static String sub_know(Connection con)
    {
        int i = 0;
        StringBuffer sb = new StringBuffer("");
        String sql = "select id,name,gradenote,subid from knowpoint order by gradenote,subid,id";
        try
        {
            PreparedStatement pstmt = con.prepareStatement(sql);
            ResultSet rs = pstmt.executeQuery();
            sb.append("<script language =\"JavaScript\">\n");
            sb.append("var gskcount;\n");
            sb.append("gskcount=0;\n");
            sb.append("grade_sub_know=new Array();\n");
            while(rs.next()) 
            {
                sb.append(String.valueOf(String.valueOf((new StringBuffer("grade_sub_know[")).append(i).append("]=new Array(\"").append(rs.getString("gradenote")).append("\",\"").append(rs.getInt("subid")).append("\",\"").append(rs.getInt("id")).append("\",\"").append(rs.getString("name")).append("\")\n"))));
                i++;
            }
            sb.append(String.valueOf(String.valueOf((new StringBuffer("gskcount=")).append(i).append("\n"))));
            sb.append("</script>\n");
        }
        catch(SQLException se)
        {
            System.out.print(se.toString());
        }
        return sb.toString();
    }

    public static String grade_sub(Connection con)
    {
        int i = 0;
        StringBuffer sb = new StringBuffer("");
        String sql = "select id,name,gradenote from subject order by gradenote,id";
        try
        {
            PreparedStatement pstmt = con.prepareStatement(sql);
            ResultSet rs = pstmt.executeQuery();
            sb.append("<script language =\"JavaScript\">\n");
            sb.append("var gscount;\n");
            sb.append("gscount=0;\n");
            sb.append("grade_sub=new Array();\n");
            while(rs.next()) 
            {
                sb.append(String.valueOf(String.valueOf((new StringBuffer("grade_sub[")).append(i).append("]=new Array(\"").append(rs.getString("gradenote")).append("\",\"").append(rs.getInt("id")).append("\",\"").append(rs.getString("name")).append("\")\n"))));
                i++;
            }
            sb.append(String.valueOf(String.valueOf((new StringBuffer("gscount=")).append(i).append("\n"))));
            sb.append("</script>\n");
        }
        catch(SQLException se)
        {
            System.out.print(se.toString());
        }
        return sb.toString();
    }

    public static void debugPrintln(String msg)
    {
        try
        {
            SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
            String now = df.format(new Date());
            File out = new File("d://debug.txt");
            FileWriter fw = new FileWriter(out, true);
            PrintWriter pw = new PrintWriter(fw, true);
            pw.println(String.valueOf(String.valueOf((new StringBuffer(String.valueOf(String.valueOf(now)))).append(" : ").append(msg))));
            fw.close();
        }
        catch(Exception e)
        {
            System.out.println(e.toString());
        }
    }
}