b43edc5ef0c0bfd1889ee738fa1843f76b3250b9
[dmaap/dbcapi.git] / src / main / java / org / onap / dmaap / dbcapi / database / TableHandler.java
1 /*-
2  * ============LICENSE_START=======================================================
3  * org.onap.dmaap
4  * ================================================================================
5  * Copyright (C) 2017 AT&T Intellectual Property. All rights reserved.
6  * ================================================================================
7  * Licensed under the Apache License, Version 2.0 (the "License");
8  * you may not use this file except in compliance with the License.
9  * You may obtain a copy of the License at
10  * 
11  *      http://www.apache.org/licenses/LICENSE-2.0
12  * 
13  * Unless required by applicable law or agreed to in writing, software
14  * distributed under the License is distributed on an "AS IS" BASIS,
15  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16  * See the License for the specific language governing permissions and
17  * limitations under the License.
18  * ============LICENSE_END=========================================================
19  */
20
21 package org.onap.dmaap.dbcapi.database;
22
23 import java.util.*;
24 import java.lang.reflect.*;
25 import java.sql.*;
26
27 class TableHandler<C>   {
28         protected ConnectionFactory cf;
29         protected boolean       haskey;
30         protected String        delstmt;
31         protected String        insorreplstmt;
32         protected String        getstmt;
33         protected String        liststmt;
34         protected String        initstmt;
35         protected Class<C>      cls;
36         protected DBFieldHandler[] fields;
37         private static Map<String, Map<String, DBFieldHandler.SqlOp>> exceptions = new HashMap<String, Map<String, DBFieldHandler.SqlOp>>();
38         public static void setSpecialCase(String dbtabname, String dbfldname, DBFieldHandler.SqlOp handler) {
39                 Map<String, DBFieldHandler.SqlOp> m = exceptions.get(dbtabname);
40                 if (m == null) {
41                         m = new HashMap<String, DBFieldHandler.SqlOp>();
42                         exceptions.put(dbtabname, m);
43                 }
44                 m.put(dbfldname, handler);
45         }
46         public static DBFieldHandler.SqlOp getSpecialCase(String dbtabname, String dbfldname) {
47                 Map<String, DBFieldHandler.SqlOp> m = exceptions.get(dbtabname);
48                 if (m != null) {
49                         return(m.get(dbfldname));
50                 }
51                 return(null);
52         }
53         protected TableHandler(Class<C> cls, String tabname, String keyname) throws Exception {
54                 this(ConnectionFactory.getDefaultInstance(), cls, tabname, keyname);
55         }
56         protected TableHandler(ConnectionFactory cf, Class<C> cls, String tabname, String keyname) throws Exception {
57                 this.cf = cf;
58                 Connection c = null;
59                 try {
60                         c = cf.get(false);
61                         setup(c.getMetaData(), cls, tabname, keyname);
62                 } finally {
63                         if (c != null) {
64                                 cf.release(c);
65                         }
66                 }
67         }
68         private void setup(DatabaseMetaData dmd, Class<C> cls, String tabname, String keyname) throws Exception {
69                 this.cls = cls;
70                 Vector<DBFieldHandler> h = new Vector<DBFieldHandler>();
71                 ResultSet rs = dmd.getColumns("", "public", tabname, null);
72                 StringBuffer sb1 = new StringBuffer();
73                 StringBuffer sb2 = new StringBuffer();
74                 StringBuffer sb3 = new StringBuffer();
75                 int     count = 0;
76                 while (rs.next()) {
77                         if (!rs.getString(3).equals(tabname)) {
78                                 continue;
79                         }
80                         String cname = rs.getString(4);
81                         if (cname.equals(keyname)) {
82                                 haskey = true;
83                                 continue;
84                         }
85                         sb1.append(", ").append(cname);
86                         sb2.append(", ?");
87                         sb3.append(", EXCLUDED.").append(cname);
88                         count++;
89                         h.add(new DBFieldHandler(cls, cname, count, getSpecialCase(tabname, cname)));
90                 }
91                 if (count == 0) {
92                         throw new SQLException("Table " + tabname + " not found");
93                 }
94                 String clist = sb1.substring(2);
95                 String qlist = sb2.substring(2);
96                 String elist = sb3.substring(2);
97                 if (keyname != null && !haskey) {
98                         throw new SQLException("Table " + tabname + " does not have key column " + keyname + " not found");
99                 }
100                 if (haskey) {
101                         count++;
102                         h.add(new DBFieldHandler(cls, keyname, count, getSpecialCase(tabname, keyname)));
103                         delstmt = "DELETE FROM " + tabname + " WHERE " + keyname + " = ?";
104                         insorreplstmt = "INSERT INTO " + tabname + " (" + clist + ", " + keyname + ") VALUES (" + qlist + ", ?) ON CONFLICT(" + keyname + ") DO UPDATE SET (" + clist + ") = (" + elist + ")";
105                         getstmt = "SELECT " + clist + ", " + keyname + " FROM " + tabname + " WHERE " + keyname + " = ?";
106                         liststmt = "SELECT " + clist + ", " + keyname + " FROM " + tabname;
107                 } else {
108                         delstmt = "DELETE FROM " + tabname;
109                         initstmt = "INSERT INTO " + tabname + " (" + clist + ") VALUES (" + qlist + ")";
110                         insorreplstmt = "UPDATE " + tabname + " SET (" + clist + ") = (" + qlist + ")";
111                         getstmt = "SELECT " + clist + ", " + keyname + " FROM " + tabname;
112                 }
113                 fields = h.toArray(new DBFieldHandler[h.size()]);
114         }
115 }