1    package net.server.servlets; 
2     
3    import java.sql.*; 
4     
5    /** 
6     * DatabaseReader Class 
7     */ 
8     
9    public class DatabaseReader { 
10    
11   // This is from mid-term 
12   //          deltaNew.setDriver("org.gjt.mm.mysql.Driver"); 
13   //        System.out.println( deltaNew.getDriver() ); 
14   //        deltaNew.setUrl("jdbc:mysql://JHVY501/test"); 
15    
16       private String driver = net.server.db.SqlBean.getDriver(); 
17    
18       private String url = net.server.db.SqlBean.getUrl(); 
19    
20    
21       private Connection cn; 
22       private Statement stmt; 
23       private ResultSet rs; 
24    
25       private String user = net.server.db.SqlBean.getUserId(); 
26       private String password = net.server.db.SqlBean.getPassword(); 
27    
28    
29       /** 
30        * Sets the Driver 
31        * 
32        * @parm            String      driver 
33        * @return       void 
34        */ 
35    
36       public void setDriver(String _driver) { 
37           driver = _driver; 
38       } 
39    
40       /** 
41        * Sets the URL 
42        * 
43        * @parm            String      url 
44        * @return       void 
45        */ 
46    
47       public void setUrl(String _url) { 
48           url = _url; 
49       } 
50    
51       /** 
52        * Sets the Connection 
53        * 
54        * @parm            String      connection 
55        * @return       void 
56        */ 
57    
58       public void setConnection(String _cn) { 
59    
60       } 
61    
62       /** 
63        * Sets the User 
64        * 
65        * @parm            String      user 
66        * @parm            String      password 
67        * @return       void 
68        */ 
69    
70       public void setUser(String _user, String _password) { 
71           user = _user; 
72           password = _password; 
73       } 
74    
75       /** 
76        * Establishes the Database Connection 
77        * 
78        * @return       void 
79        * @throws       java.lang.ClassNotFoundException, Exception 
80        */ 
81    
82       public void openDatabase() throws ClassNotFoundException, 
83               Exception { 
84    
85           System.out.println("Connecting to Database in openDatabase Method"); 
86           System.out.println("URL is " + url + " Driver is " + driver); 
87           //User is " + user + "\npassword is " + password ); 
88    
89           try { 
90               Class.forName(driver); 
91           } catch (Exception E) { 
92               System.out.println("Failed on the class name"); 
93           } 
94    
95           try { 
96               cn = DriverManager.getConnection(url, user, password); 
97           } catch (Exception E) { 
98               System.out.println("Failed on the connection"); 
99           } 
100   
101          stmt = cn.createStatement(); 
102   
103      } 
104   
105      /** 
106       * Closes the Database Connection 
107       * 
108       * @return       void 
109       */ 
110   
111      public void closeDatabase() { 
112          try { 
113              stmt.close(); 
114              cn.close(); 
115          } catch (SQLException sqle) { 
116              sqle.printStackTrace(); 
117          } 
118      } 
119   
120      /** 
121       * Return true/false 
122       * 
123       * @parm         String        sql 
124       * @return       boolean 
125       */ 
126   
127      public boolean checkRecordExists(String sql) { 
128   
129          try { 
130              openDatabase(); 
131              rs = stmt.executeQuery(sql); 
132              closeDatabase(); 
133              return rs.next(); 
134          } catch (ClassNotFoundException cnf) { 
135              System.out.println("\n ClassNotFound"); 
136              cnf.printStackTrace(); 
137              return false; 
138          } catch (SQLException sqle) { 
139              System.out.println("\n checkRecordExists Failure"); 
140              sqle.printStackTrace(); 
141              return false; 
142          } catch (Exception e) { 
143              System.out.println("\n Exception"); 
144              e.printStackTrace(); 
145              return false; 
146          } 
147      } 
148   
149  } 
150   
151   
152   
153