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.lang.reflect.*;
  24
  25 import java.sql.Connection;
  26 import java.sql.DatabaseMetaData;
  27 import java.sql.ResultSet;
  28 import java.sql.SQLException;
  29 import java.util.HashMap;
  30 import java.util.Map;
  31 import java.util.Vector;
  32
  33 class TableHandler<C>   {
  34         protected ConnectionFactory cf;
  35         protected boolean       haskey;
  36         protected String        delstmt;
  37         protected String        insorreplstmt;
  38         protected String        getstmt;
  39         protected String        liststmt;
  40         protected String        initstmt;
  41         protected Class<C>      cls;
  42         protected DBFieldHandler[] fields;
  43         private static Map<String, Map<String, DBFieldHandler.SqlOp>> exceptions = new HashMap<String, Map<String, DBFieldHandler.SqlOp>>();
  44         public static void setSpecialCase(String dbtabname, String dbfldname, DBFieldHandler.SqlOp handler) {
  45                 Map<String, DBFieldHandler.SqlOp> m = exceptions.get(dbtabname);
  46                 if (m == null) {
  47                         m = new HashMap<String, DBFieldHandler.SqlOp>();
  48                         exceptions.put(dbtabname, m);
  49                 }
  50                 m.put(dbfldname, handler);
  51         }
  52         public static DBFieldHandler.SqlOp getSpecialCase(String dbtabname, String dbfldname) {
  53                 Map<String, DBFieldHandler.SqlOp> m = exceptions.get(dbtabname);
  54                 if (m != null) {
  55                         return(m.get(dbfldname));
  56                 }
  57                 return(null);
  58         }
  59         protected TableHandler(Class<C> cls, String tabname, String keyname) throws Exception {
  60                 this(ConnectionFactory.getDefaultInstance(), cls, tabname, keyname);
  61         }
  62         protected TableHandler(ConnectionFactory cf, Class<C> cls, String tabname, String keyname) throws Exception {
  63                 this.cf = cf;
  64                 Connection c = null;
  65                 try {
  66                         c = cf.get(false);
  67                         setup(c.getMetaData(), cls, tabname, keyname);
  68                 } finally {
  69                         if (c != null) {
  70                                 cf.release(c);
  71                         }
  72                 }
  73         }
  74         private void setup(DatabaseMetaData dmd, Class<C> cls, String tabname, String keyname) throws Exception {
  75                 this.cls = cls;
  76                 Vector<DBFieldHandler> h = new Vector<DBFieldHandler>();
  77                 String qualifiedTableName = String.format( "%s.%s", cf.getSchema(), tabname );
  78                 ResultSet rs = dmd.getColumns("", cf.getSchema(), tabname, null);
  79                 StringBuffer sb1 = new StringBuffer();
  80                 StringBuffer sb2 = new StringBuffer();
  81                 StringBuffer sb3 = new StringBuffer();
  82                 int     count = 0;
  83                 while (rs.next()) {
  84                         if (!rs.getString(3).equals(tabname)) {
  85                                 continue;
  86                         }
  87                         String cname = rs.getString(4);
  88                         if (cname.equals(keyname)) {
  89                                 haskey = true;
  90                                 continue;
  91                         }
  92                         sb1.append(", ").append(cname);
  93                         sb2.append(", ?");
  94                         sb3.append(", EXCLUDED.").append(cname);
  95                         count++;
  96                         h.add(new DBFieldHandler(cls, cname, count, getSpecialCase(tabname, cname)));
  97                 }
  98                 if (count == 0) {
  99                         throw new SQLException("Table " + tabname + " not found");
 100                 }
 101                 String clist = sb1.substring(2);
 102                 String qlist = sb2.substring(2);
 103                 String elist = sb3.substring(2);
 104                 if (keyname != null && !haskey) {
 105                         throw new SQLException("Table " + tabname + " does not have key column " + keyname + " not found");
 106                 }
 107                 if (haskey) {
 108                         count++;
 109                         h.add(new DBFieldHandler(cls, keyname, count, getSpecialCase(tabname, keyname)));
 110                         delstmt = "DELETE FROM " + qualifiedTableName + " WHERE " + keyname + " = ?";
 111                         insorreplstmt = "INSERT INTO " + qualifiedTableName + " (" + clist + ", " + keyname + ") VALUES (" + qlist + ", ?) ON CONFLICT(" + keyname + ") DO UPDATE SET (" + clist + ") = (" + elist + ")";
 112                         getstmt = "SELECT " + clist + ", " + keyname + " FROM " + qualifiedTableName + " WHERE " + keyname + " = ?";
 113                         liststmt = "SELECT " + clist + ", " + keyname + " FROM " + qualifiedTableName;
 114                 } else {
 115                         delstmt = "DELETE FROM " + qualifiedTableName;
 116                         initstmt = "INSERT INTO " + qualifiedTableName + " (" + clist + ") VALUES (" + qlist + ")";
 117                         insorreplstmt = "UPDATE " + qualifiedTableName + " SET (" + clist + ") = (" + qlist + ")";
 118                         getstmt = "SELECT " + clist + ", " + keyname + " FROM " + qualifiedTableName;
 119                 }
 120                 fields = h.toArray(new DBFieldHandler[h.size()]);
 121         }
 122 }