This patch fixes the 0-based/1-based result set indexing problem for

bmomjian · bmomjian · commit d3ef75368638 · 2000-06-09T17:27:57.000Z
absolute. It also makes it more compliant with the interface specification in Sun's documentation; 1. absolute(0) should throw an exception. 2. absolute(>num-records) should set the current row to after the last record in addition to returning false. 3. absolute(<num-records) should set the current row to before the first record in addition to returning false. These operations in the existing code just return false and don't change current_row. These changes required a minor change to relative(int) since it calls absolute(int) The attached patch is against the cvs repository tree as of this morning. Also, who is in charge of maintaining the jdbc driver? I'm working on getArray for the jdbc2 driver, but it's going to require three more classes to be added to the driver, and thus three more source files in the repository. Is there someone I can contact directly to ask about this? Travis Bauer | CS Grad Student | IU |www.cs.indiana.edu/~trbauer
diff --git a/src/interfaces/jdbc/org/postgresql/jdbc2/ResultSet.java b/src/interfaces/jdbc/org/postgresql/jdbc2/ResultSet.java
@@ -801,16 +801,34 @@ public int findColumn(String columnName) throws SQLException
     
     public boolean absolute(int index) throws SQLException
     {
-	// Peter: Added because negative indices read from the end of the
-	// ResultSet
-	if(index<0)
-	    index=rows.size()+index;
-	
-	if (index > rows.size())
+	// index is 1-based, but internally we use 0-based indices
+	int internalIndex;
+
+	if (index==0)
+	    throw new SQLException("Cannot move to index of 0");	
+
+	//if index<0, count from the end of the result set, but check
+	//to be sure that it is not beyond the first index
+	if (index<0) 
+	    if (index>=-rows.size())
+		internalIndex=rows.size()+index;
+	    else {
+		beforeFirst();
+		return false;
+	    }
+		
+	//must be the case that index>0, 
+	//find the correct place, assuming that 
+	//the index is not too large
+	if (index<=rows.size())
+	    internalIndex = index-1;
+	else {
+	    afterLast();
 	    return false;
-	
-	current_row=index;
-	this_row = (byte [][])rows.elementAt(index);
+	}
+
+	current_row=internalIndex;
+	this_row = (byte [][])rows.elementAt(internalIndex);
 	return true;
     }
     
@@ -1041,7 +1059,8 @@ public void refreshRow() throws SQLException
     // Peter: Implemented in 7.0
     public boolean relative(int rows) throws SQLException
     {
-	return absolute(current_row+rows);
+	//have to add 1 since absolute expects a 1-based index
+	return absolute(current_row+1+rows);
     }
     
     public boolean rowDeleted() throws SQLException
