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                 String qualifiedTableName = String.format( "%s.%s", cf.getSchema(), tabname );
  72                 ResultSet rs = dmd.getColumns("", cf.getSchema(), tabname, null);
  73                 StringBuffer sb1 = new StringBuffer();
  74                 StringBuffer sb2 = new StringBuffer();
  75                 StringBuffer sb3 = new StringBuffer();
  76                 int     count = 0;
  77                 while (rs.next()) {
  78                         if (!rs.getString(3).equals(tabname)) {
  79                                 continue;
  80                         }
  81                         String cname = rs.getString(4);
  82                         if (cname.equals(keyname)) {
  83                                 haskey = true;
  84                                 continue;
  85                         }
  86                         sb1.append(", ").append(cname);
  87                         sb2.append(", ?");
  88                         sb3.append(", EXCLUDED.").append(cname);
  89                         count++;
  90                         h.add(new DBFieldHandler(cls, cname, count, getSpecialCase(tabname, cname)));
  91                 }
  92                 if (count == 0) {
  93                         throw new SQLException("Table " + tabname + " not found");
  94                 }
  95                 String clist = sb1.substring(2);
  96                 String qlist = sb2.substring(2);
  97                 String elist = sb3.substring(2);
  98                 if (keyname != null && !haskey) {
  99                         throw new SQLException("Table " + tabname + " does not have key column " + keyname + " not found");
 100                 }
 101                 if (haskey) {
 102                         count++;
 103                         h.add(new DBFieldHandler(cls, keyname, count, getSpecialCase(tabname, keyname)));
 104                         delstmt = "DELETE FROM " + qualifiedTableName + " WHERE " + keyname + " = ?";
 105                         insorreplstmt = "INSERT INTO " + qualifiedTableName + " (" + clist + ", " + keyname + ") VALUES (" + qlist + ", ?) ON CONFLICT(" + keyname + ") DO UPDATE SET (" + clist + ") = (" + elist + ")";
 106                         getstmt = "SELECT " + clist + ", " + keyname + " FROM " + qualifiedTableName + " WHERE " + keyname + " = ?";
 107                         liststmt = "SELECT " + clist + ", " + keyname + " FROM " + qualifiedTableName;
 108                 } else {
 109                         delstmt = "DELETE FROM " + qualifiedTableName;
 110                         initstmt = "INSERT INTO " + qualifiedTableName + " (" + clist + ") VALUES (" + qlist + ")";
 111                         insorreplstmt = "UPDATE " + qualifiedTableName + " SET (" + clist + ") = (" + qlist + ")";
 112                         getstmt = "SELECT " + clist + ", " + keyname + " FROM " + qualifiedTableName;
 113                 }
 114                 fields = h.toArray(new DBFieldHandler[h.size()]);
 115         }
 116 }