ResultSet.next() and previous() incremented or decremented the

internal current_row variable regardless of wether they succeeded or
not.  This generated some ArrayIndexOutOfBoundsExceptions when the
errorneous adjustment current_row led to out of range values.

Per report from Fischer Krisztian.

src/interfaces/jdbc/org/postgresql/jdbc1/AbstractJdbc1ResultSet.java

@@ -9,7 +9,7 @@
  * Copyright (c) 2003, PostgreSQL Global Development Group
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/interfaces/jdbc/org/postgresql/jdbc1/Attic/AbstractJdbc1ResultSet.java,v 1.22.2.1 2003/12/12 17:59:08 davec Exp $
+ *	  $Header: /cvsroot/pgsql/src/interfaces/jdbc/org/postgresql/jdbc1/Attic/AbstractJdbc1ResultSet.java,v 1.22.2.2 2004/02/03 05:25:36 jurka Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -137,11 +137,13 @@ public abstract class AbstractJdbc1ResultSet implements BaseResultSet
 		if (rows == null)
 			throw new PSQLException("postgresql.con.closed", PSQLState.CONNECTION_DOES_NOT_EXIST);
 
-		if (++current_row >= rows.size())
+		if (current_row+1 >= rows.size())
 		{
  			String cursorName = statement.getFetchingCursorName();
-			if (cursorName == null || lastFetchSize == 0 || rows.size() < lastFetchSize)
+			if (cursorName == null || lastFetchSize == 0 || rows.size() < lastFetchSize) {
+				current_row = rows.size();
 				return false;  // Not doing a cursor-based fetch or the last fetch was the end of the query
+			}
  
   			// Use the ref to the statement to get
   			// the details we need to do another cursor
@@ -167,6 +169,8 @@ public abstract class AbstractJdbc1ResultSet implements BaseResultSet
 
 			// Otherwise reset the counter and let it go on...
 			current_row = 0;
+		} else {
+			current_row++;
 		}
 
 		this_row = (byte [][])rows.elementAt(current_row);

src/interfaces/jdbc/org/postgresql/jdbc2/AbstractJdbc2ResultSet.java

@@ -9,7 +9,7 @@
  * Copyright (c) 2003, PostgreSQL Global Development Group
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/interfaces/jdbc/org/postgresql/jdbc2/Attic/AbstractJdbc2ResultSet.java,v 1.25.2.2 2003/12/18 03:35:55 davec Exp $
+ *	  $Header: /cvsroot/pgsql/src/interfaces/jdbc/org/postgresql/jdbc2/Attic/AbstractJdbc2ResultSet.java,v 1.25.2.3 2004/02/03 05:25:37 jurka Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -490,8 +490,12 @@ public abstract class AbstractJdbc2ResultSet extends org.postgresql.jdbc1.Abstra
 
 	public boolean previous() throws SQLException
 	{
-		if (--current_row < 0)
+		if (current_row-1 < 0) {
+			current_row = -1;
 			return false;
+		} else {
+			current_row--;
+		}
 		this_row = (byte[][]) rows.elementAt(current_row);
 		rowBuffer = new byte[this_row.length][];
 		System.arraycopy(this_row, 0, rowBuffer, 0, this_row.length);

src/interfaces/jdbc/org/postgresql/test/jdbc2/ResultSetTest.java

@@ -4,6 +4,7 @@ import org.postgresql.test.TestUtil;
 import java.sql.Connection;
 import java.sql.ResultSet;
 import java.sql.Statement;
+import java.sql.SQLException;
 
 import junit.framework.TestCase;
 
@@ -285,5 +286,48 @@ public class ResultSetTest extends TestCase
 				fail("Exception expected.");
 		}
 	}
-       
+
+	public void testZeroRowResultPositioning() throws SQLException
+	{
+		Statement stmt = con.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE, ResultSet.CONCUR_UPDATABLE);
+		ResultSet rs = stmt.executeQuery("SELECT * FROM pg_database WHERE datname='nonexistantdatabase'");
+		assertEquals(rs.previous(),false);
+		assertEquals(rs.previous(),false);
+		assertEquals(rs.next(),false);
+		assertEquals(rs.next(),false);
+		assertEquals(rs.next(),false);
+		assertEquals(rs.next(),false);
+		assertEquals(rs.next(),false);
+		assertEquals(rs.previous(),false);
+		assertEquals(rs.first(),false);
+		assertEquals(rs.last(),false);
+		assertEquals(rs.getRow(),0);
+		assertEquals(rs.absolute(1),false);
+		assertEquals(rs.relative(1),false);
+		assertEquals(rs.isBeforeFirst(),false);
+		assertEquals(rs.isAfterLast(),false);
+		assertEquals(rs.isFirst(),false);
+		assertEquals(rs.isLast(),false);
+		rs.close();
+		stmt.close();
+	}
+
+	public void testRowResultPositioning() throws SQLException
+	{
+		Statement stmt = con.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE, ResultSet.CONCUR_UPDATABLE);
+		// Create a one row result set.
+		ResultSet rs = stmt.executeQuery("SELECT * FROM pg_database WHERE datname='template1'");
+		assertTrue(rs.isBeforeFirst());
+		assertTrue(rs.next());
+		assertTrue(rs.isFirst());
+		assertTrue(rs.isLast());
+		assertTrue(!rs.next());
+		assertTrue(rs.isAfterLast());
+		assertTrue(rs.previous());
+		assertTrue(rs.absolute(1));
+		rs.close();
+		stmt.close();
+	}
+
 }
+