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This patch merges the identical methods from the JDBC1 and JDBC2
connection implementations (org.postgresql.jdbc[1|2].Connection) into their superclass (org.postgresql.Connection). It also changes the close() methods of Connection and PG_Stream, so that PG_Stream no longer is responsible for sending the termination packet 'X' to the backend. I figured that protocol-level stuff like that belonged in Connection more than in PG_Stream. Anders Bengtsson
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4 files changed

+239
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4 files changed

+239
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‎src/interfaces/jdbc/org/postgresql/Connection.java

Lines changed: 236 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -11,7 +11,7 @@
1111
import org.postgresql.core.Encoding;
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1313
/**
14-
* $Id: Connection.java,v 1.20 2001/07/21 18:56:17 momjian Exp $
14+
* $Id: Connection.java,v 1.21 2001/07/30 14:51:19 momjian Exp $
1515
*
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* This abstract class is used by org.postgresql.Driver to open either the JDBC1 or
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* JDBC2 versions of the Connection class.
@@ -76,6 +76,11 @@ public abstract class Connection
7676
// Now handle notices as warnings, so things like "show" now work
7777
public SQLWarning firstWarning = null;
7878

79+
/**
80+
* Cache of the current isolation level
81+
*/
82+
private int isolationLevel = java.sql.Connection.TRANSACTION_READ_COMMITTED;
83+
7984
// The PID an cancellation key we get from the backend process
8085
public int pid;
8186
public int ckey;
@@ -788,7 +793,236 @@ private void initObjectTypes()
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*/
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protected abstract java.sql.ResultSet getResultSet(org.postgresql.Connection conn,java.sql.Statement stat, Field[] fields, Vector tuples, String status, int updateCount,int insertOID) throws SQLException;
790795

791-
public abstract void close() throws SQLException;
796+
/**
797+
* In some cases, it is desirable to immediately release a Connection's
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* database and JDBC resources instead of waiting for them to be
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* automatically released (cant think why off the top of my head)
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*
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* <B>Note:</B> A Connection is automatically closed when it is
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* garbage collected. Certain fatal errors also result in a closed
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* connection.
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*
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* @exception SQLException if a database access error occurs
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*/
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public void close() throws SQLException {
808+
if (pg_stream != null) {
809+
try {
810+
pg_stream.SendChar('X');
811+
pg_stream.flush();
812+
pg_stream.close();
813+
} catch (IOException e) {}
814+
pg_stream = null;
815+
}
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}
817+
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/**
819+
* A driver may convert the JDBC sql grammar into its system's
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* native SQL grammar prior to sending it; nativeSQL returns the
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* native form of the statement that the driver would have sent.
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*
823+
* @param sql a SQL statement that may contain one or more '?'
824+
* parameter placeholders
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* @return the native form of this statement
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* @exception SQLException if a database access error occurs
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*/
828+
public String nativeSQL(String sql) throws SQLException {
829+
return sql;
830+
}
831+
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/**
833+
* The first warning reported by calls on this Connection is
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* returned.
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*
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* <B>Note:</B> Sebsequent warnings will be changed to this
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* SQLWarning
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*
839+
* @return the first SQLWarning or null
840+
* @exception SQLException if a database access error occurs
841+
*/
842+
public SQLWarning getWarnings() throws SQLException {
843+
return firstWarning;
844+
}
845+
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/**
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* After this call, getWarnings returns null until a new warning
848+
* is reported for this connection.
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*
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* @exception SQLException if a database access error occurs
851+
*/
852+
public void clearWarnings() throws SQLException {
853+
firstWarning = null;
854+
}
855+
856+
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/**
858+
* You can put a connection in read-only mode as a hunt to enable
859+
* database optimizations
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*
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* <B>Note:</B> setReadOnly cannot be called while in the middle
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* of a transaction
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*
864+
* @param readOnly - true enables read-only mode; false disables it
865+
* @exception SQLException if a database access error occurs
866+
*/
867+
public void setReadOnly(boolean readOnly) throws SQLException {
868+
this.readOnly = readOnly;
869+
}
870+
871+
/**
872+
* Tests to see if the connection is in Read Only Mode. Note that
873+
* we cannot really put the database in read only mode, but we pretend
874+
* we can by returning the value of the readOnly flag
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*
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* @return true if the connection is read only
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* @exception SQLException if a database access error occurs
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*/
879+
public boolean isReadOnly() throws SQLException {
880+
return readOnly;
881+
}
882+
883+
/**
884+
* If a connection is in auto-commit mode, than all its SQL
885+
* statements will be executed and committed as individual
886+
* transactions. Otherwise, its SQL statements are grouped
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* into transactions that are terminated by either commit()
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* or rollback(). By default, new connections are in auto-
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* commit mode. The commit occurs when the statement completes
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* or the next execute occurs, whichever comes first. In the
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* case of statements returning a ResultSet, the statement
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* completes when the last row of the ResultSet has been retrieved
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* or the ResultSet has been closed. In advanced cases, a single
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* statement may return multiple results as well as output parameter
895+
* values. Here the commit occurs when all results and output param
896+
* values have been retrieved.
897+
*
898+
* @param autoCommit - true enables auto-commit; false disables it
899+
* @exception SQLException if a database access error occurs
900+
*/
901+
public void setAutoCommit(boolean autoCommit) throws SQLException {
902+
if (this.autoCommit == autoCommit)
903+
return;
904+
if (autoCommit)
905+
ExecSQL("end");
906+
else {
907+
ExecSQL("begin");
908+
doIsolationLevel();
909+
}
910+
this.autoCommit = autoCommit;
911+
}
912+
913+
/**
914+
* gets the current auto-commit state
915+
*
916+
* @return Current state of the auto-commit mode
917+
* @exception SQLException (why?)
918+
* @see setAutoCommit
919+
*/
920+
public boolean getAutoCommit() throws SQLException {
921+
return this.autoCommit;
922+
}
923+
924+
/**
925+
* The method commit() makes all changes made since the previous
926+
* commit/rollback permanent and releases any database locks currently
927+
* held by the Connection. This method should only be used when
928+
* auto-commit has been disabled. (If autoCommit == true, then we
929+
* just return anyhow)
930+
*
931+
* @exception SQLException if a database access error occurs
932+
* @see setAutoCommit
933+
*/
934+
public void commit() throws SQLException {
935+
if (autoCommit)
936+
return;
937+
ExecSQL("commit");
938+
autoCommit = true;
939+
ExecSQL("begin");
940+
doIsolationLevel();
941+
autoCommit = false;
942+
}
943+
944+
/**
945+
* The method rollback() drops all changes made since the previous
946+
* commit/rollback and releases any database locks currently held by
947+
* the Connection.
948+
*
949+
* @exception SQLException if a database access error occurs
950+
* @see commit
951+
*/
952+
public void rollback() throws SQLException {
953+
if (autoCommit)
954+
return;
955+
ExecSQL("rollback");
956+
autoCommit = true;
957+
ExecSQL("begin");
958+
doIsolationLevel();
959+
autoCommit = false;
960+
}
961+
962+
/**
963+
* Get this Connection's current transaction isolation mode.
964+
*
965+
* @return the current TRANSACTION_* mode value
966+
* @exception SQLException if a database access error occurs
967+
*/
968+
public int getTransactionIsolation() throws SQLException {
969+
clearWarnings();
970+
ExecSQL("show xactisolevel");
971+
972+
SQLWarning warning = getWarnings();
973+
if (warning != null) {
974+
String message = warning.getMessage();
975+
clearWarnings();
976+
if (message.indexOf("READ COMMITTED") != -1)
977+
return java.sql.Connection.TRANSACTION_READ_COMMITTED;
978+
else if (message.indexOf("READ UNCOMMITTED") != -1)
979+
return java.sql.Connection.TRANSACTION_READ_UNCOMMITTED;
980+
else if (message.indexOf("REPEATABLE READ") != -1)
981+
return java.sql.Connection.TRANSACTION_REPEATABLE_READ;
982+
else if (message.indexOf("SERIALIZABLE") != -1)
983+
return java.sql.Connection.TRANSACTION_SERIALIZABLE;
984+
}
985+
return java.sql.Connection.TRANSACTION_READ_COMMITTED;
986+
}
987+
988+
/**
989+
* You can call this method to try to change the transaction
990+
* isolation level using one of the TRANSACTION_* values.
991+
*
992+
* <B>Note:</B> setTransactionIsolation cannot be called while
993+
* in the middle of a transaction
994+
*
995+
* @param level one of the TRANSACTION_* isolation values with
996+
* the exception of TRANSACTION_NONE; some databases may
997+
* not support other values
998+
* @exception SQLException if a database access error occurs
999+
* @see java.sql.DatabaseMetaData#supportsTransactionIsolationLevel
1000+
*/
1001+
public void setTransactionIsolation(int level) throws SQLException {
1002+
isolationLevel = level;
1003+
doIsolationLevel();
1004+
}
1005+
1006+
/**
1007+
* Helper method used by setTransactionIsolation(), commit(), rollback()
1008+
* and setAutoCommit(). This sets the current isolation level.
1009+
*/
1010+
protected void doIsolationLevel() throws SQLException {
1011+
String q = "SET TRANSACTION ISOLATION LEVEL";
1012+
1013+
switch(isolationLevel) {
1014+
case java.sql.Connection.TRANSACTION_READ_COMMITTED:
1015+
ExecSQL(q + " READ COMMITTED");
1016+
return;
1017+
1018+
case java.sql.Connection.TRANSACTION_SERIALIZABLE:
1019+
ExecSQL(q + " SERIALIZABLE");
1020+
return;
1021+
1022+
default:
1023+
throw new PSQLException("postgresql.con.isolevel",new Integer(isolationLevel));
1024+
}
1025+
}
7921026

7931027
/**
7941028
* A sub-space of this Connection's database may be selected by

‎src/interfaces/jdbc/org/postgresql/PG_Stream.java

Lines changed: 1 addition & 3 deletions
Original file line numberDiff line numberDiff line change
@@ -10,7 +10,7 @@
1010
import org.postgresql.util.*;
1111

1212
/**
13-
* $Id: PG_Stream.java,v 1.10 2001/07/21 18:52:10 momjian Exp $
13+
* $Id: PG_Stream.java,v 1.11 2001/07/30 14:51:19 momjian Exp $
1414
*
1515
* This class is used by Connection & PGlobj for communicating with the
1616
* backend.
@@ -346,8 +346,6 @@ public void flush() throws SQLException
346346
*/
347347
public void close() throws IOException
348348
{
349-
pg_output.write("X".getBytes());
350-
pg_output.flush();
351349
pg_output.close();
352350
pg_input.close();
353351
connection.close();

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