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The Open Source version of the IBM Toolbox for Java
///////////////////////////////////////////////////////////////////////////////
//
// JTOpen (IBM Toolbox for Java - OSS version)
//
// Filename: DBExtendedColumnDescriptors.java
//
// The source code contained herein is licensed under the IBM Public License
// Version 1.0, which has been approved by the Open Source Initiative.
// Copyright (C) 1997-2001 International Business Machines Corporation and
// others. All rights reserved.
//
///////////////////////////////////////////////////////////////////////////////
package com.ibm.as400.access;
import java.sql.SQLException;
/**
Provides access to the package info portion of the reply data stream.
**/
class DBExtendedColumnDescriptors {
private static final String copyright = "Copyright (C) 1997-2001 International Business Machines Corporation and others.";
private byte[] data_;
private int offset_;
/**
Constructs a new DBExtendedColumnDescriptors object. It initializes
the variables using the data provided.
* @param data
* @param offset
**/
public DBExtendedColumnDescriptors (byte[] data,
int offset)
{
data_ = data;
offset_ = offset;
}
//---------------------------------------------------------
// The following structure is used to determine the amount
// needed to be added to the offset to get the appropriate
// data.
//
// offset+ field length
//
// 0 # of columns 4 bytes
// 4 reserved 6 bytes
//
// 10 extended column descriptor (repeated for each column)
// 0 fixed data 4 bytes
// 1 byte Updateable
// 1 byte Searchable
// 2 bytes
// 1 bit Identity column?
// 1 bit Column is part of an index?
// 1 bit Column is a lone unique index?
// 1 bit Column is part of a unique index attribute?
// 4 offset from beginning to variable data 4 bytes
// 8 length of variable data 4 bytes
// 12 reserved (alignment) 4 bytes
//
// (#col*16) 0 length of the column descriptor 4 bytes
// +10 4 code point of column descriptor 2 bytes
// 6 CCSID (for label only) 2 bytes
// 6 value of column descriptor n bytes
//
// Note: these offsets are in terms of the start
// of the LL for this parameter (i.e.
// actually count from (offset_ - 6).
//
//---------------------------------------------------------
public int getAttributeBitmap (int columnIndex)
{
return BinaryConverter.byteArrayToShort (data_, offset_ + getExtendedColumnDescriptorOffset (columnIndex)); //@A1C
}
//@A1D public int getCCSID ()
//@A1D {
//@A1D return BinaryConverter.byteArrayToShort (data_, offset_ + 4);
//@A1D }
public DBColumnDescriptorsDataFormat getColumnDescriptors (int columnIndex, SQLConversionSettings settings) //@Q8C
throws SQLException
{
// if variable column info length is 0, then no variable length column information
// was returned
int variableColumnInfoLength = getVariableColumnInfoLength(columnIndex);
if (variableColumnInfoLength > 0) {
int offsetToDescriptor = getVariableColumnInfoOffset (columnIndex);
DBColumnDescriptorsDataFormat columnDescriptorsDataFormat = new DBColumnDescriptorsDataFormat(settings); //@Q8C
columnDescriptorsDataFormat.overlay (data_, ((offset_ - 6) + offsetToDescriptor), variableColumnInfoLength);
return columnDescriptorsDataFormat;
}
else
return null;
}
// Fix for JTOpen Bug 4034 - The CCSID for a column label may be 65535, if that is the case, we want to use the server job's ccsid.
public DBColumnDescriptorsDataFormat getColumnDescriptors (int columnIndex, ConvTable convTable, SQLConversionSettings settings) //@Q8C
throws SQLException
{
// If columnIndex < number of columns, we might be using a stale extended descriptor
// (due to a bug in ZDA prior to November 2015).
//
if (columnIndex <= getNumberOfColumns()) {
// if variable column info length is 0, then no variable length column information
// was returned
int variableColumnInfoLength = getVariableColumnInfoLength(columnIndex);
if (variableColumnInfoLength > 0) {
int offsetToDescriptor = getVariableColumnInfoOffset (columnIndex);
DBColumnDescriptorsDataFormat columnDescriptorsDataFormat = new DBColumnDescriptorsDataFormat(convTable.getCcsid(), settings); //@Q8C
columnDescriptorsDataFormat.overlay (data_, ((offset_ - 6) + offsetToDescriptor), variableColumnInfoLength);
return columnDescriptorsDataFormat;
}
else
return null;
} else {
return null; /* Column index > number of columns */
}
}
private int getExtendedColumnDescriptorOffset (int columnIndex)
{
return(((columnIndex-1) * 16) + 10); //@A1C
}
private int getVariableColumnInfoLength (int columnIndex)
{
return BinaryConverter.byteArrayToInt (data_, (offset_ + getExtendedColumnDescriptorOffset (columnIndex) + 8));
}
private int getVariableColumnInfoOffset (int columnIndex)
{
return BinaryConverter.byteArrayToInt (data_, (offset_ + getExtendedColumnDescriptorOffset (columnIndex) + 4));
}
int getNumberOfColumns ()
{
return BinaryConverter.byteArrayToInt (data_, offset_);
}
byte getSearchable (int columnIndex)
{
return data_[offset_ + getExtendedColumnDescriptorOffset (columnIndex) + 1];
}
byte getUpdateable (int columnIndex)
{
return data_[offset_ + getExtendedColumnDescriptorOffset (columnIndex)];
}
}