Quadcap Embeddable Database

com/quadcap/sql/Row.java

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package com.quadcap.sql;

/* Copyright 1999 - 2003 Quadcap Software.  All rights reserved.
 *
 * This software is distributed under the Quadcap Free Software License.
 * This software may be used or modified for any purpose, personal or
 * commercial.  Open Source redistributions are permitted.  Commercial
 * redistribution of larger works derived from, or works which bundle
 * this software requires a "Commercial Redistribution License"; see
 * http://www.quadcap.com/purchase.
 *
 * Redistributions qualify as "Open Source" under  one of the following terms:
 *   
 *    Redistributions are made at no charge beyond the reasonable cost of
 *    materials and delivery.
 *
 *    Redistributions are accompanied by a copy of the Source Code or by an
 *    irrevocable offer to provide a copy of the Source Code for up to three
 *    years at the cost of materials and delivery.  Such redistributions
 *    must allow further use, modification, and redistribution of the Source
 *    Code under substantially the same terms as this license.
 *
 * Redistributions of source code must retain the copyright notices as they
 * appear in each source code file, these license terms, and the
 * disclaimer/limitation of liability set forth as paragraph 6 below.
 *
 * Redistributions in binary form must reproduce this Copyright Notice,
 * these license terms, and the disclaimer/limitation of liability set
 * forth as paragraph 6 below, in the documentation and/or other materials
 * provided with the distribution.
 *
 * The Software is provided on an "AS IS" basis.  No warranty is
 * provided that the Software is free of defects, or fit for a
 * particular purpose.  
 *
 * Limitation of Liability. Quadcap Software shall not be liable
 * for any damages suffered by the Licensee or any third party resulting
 * from use of the Software.
 */

import java.io.Externalizable;
import java.io.IOException;
import java.io.ObjectInput;
import java.io.ObjectOutput;

import java.util.ArrayList;

import java.sql.SQLException;

import com.quadcap.sql.types.Type;
import com.quadcap.sql.types.Value;
import com.quadcap.sql.types.ValueBlob;

import com.quadcap.util.Debug;

/**
 * Essentially, a vector with one-based indices.
 *
 * @author Stan Bailes
 */
public class Row {
    int                                 blobCnt         = 0;
    ArrayList                           v               = null;

    /**
     * Default constructor
     */
    public Row() { v = new ArrayList(); }

    /**
     * Construct an empty row with the specified number of columns
     */
    public Row(int size) {
        this.v = new ArrayList(size);
        while (v.size() < size) v.add(null);
    }

    /**
     * Construct a row as a copy of another row.
     */
    public Row(Row r, Tuple tuple) throws SQLException {
        v = new ArrayList();
        for (int i = 1; i <= r.size(); i++) {
            Value rv = r.item(i);
            if (tuple != null) {
                Type type = tuple.getColumn(i).getType();
                Value v1 = type.convert(rv);
                rv = v1;
            }
            if (rv instanceof ValueBlob) blobCnt++;
            v.add(rv);
        }
    }

    /**
     * Construct a row using a ArrayList of values.  The vector is zero-based,
     * even though the row is one-based!
     */
    public Row(ArrayList v) {
        this.v = v;
        for (int i = 0; i < v.size(); i++) {
            if (v.get(i) instanceof ValueBlob) blobCnt++;
        }            
    }

    /**
     * Return the number of values in this row.
     */
    public int size() { return v.size(); }

    /**
     * Return the number of BLOB values in this row.  (We can shortcut
     * some possibly lengthy operations if we know there are no blobs)
     */
    public int getBlobCount() throws IOException { return blobCnt; }

    /**
     * Return the specified value (one-based) from the row.
     */
    public Value item(int i) throws SQLException {
        if (i < 1 || i > v.size()) {
            throw new SQLException("bad column: " + i, "42000");
        }
        return (Value)v.get(i-1);
    }

    /**
     * Non-checked access: return the specified value (one-based) from the row.
     */
    public Value getItem(int i) {
        return (Value)v.get(i-1);
    }

    /**
     * Set value in the specified position (one-based) to a new value
     */
    public void set(int i, Value val) throws SQLException {
        final int idx = i-1;
        if (v.get(idx) instanceof ValueBlob) blobCnt--;
        if (val instanceof ValueBlob) blobCnt++;
        v.set(idx, val);
        //#ifdef TRACE
        if (Trace.bit(7)) {
            Debug.println("Row.set(" + i + "), " + blobCnt + " blobs");
        }
        //#endif
    }

    /**
     * Is the specified element updatable? 
     */
    public boolean isUpdateable(int i) {
        return true;
    }
    
    public void addElement(Value val) {
        if (val instanceof ValueBlob) blobCnt++;
        v.add(val);
    }

    //#ifdef DEBUG
    public String toString() {
        StringBuffer sb = new StringBuffer();
        sb.append("{");
        for (int i = 1; i <= size(); i++) {
            if (i > 1) sb.append(",");
            try {
                Value vx = item(i);
                //sb.append(v.getType().getTypeName());
                //sb.append(":");
                sb.append(vx.toString());
            } catch (Throwable e) {
                sb.append("<" + e.toString() + ">");
            }
        }
        sb.append("}");
        return sb.toString();
    }
    //#endif
}