secondo/Javagui/viewer/update2/Tuple.java

//This file is part of SECONDO.

//Copyright (C) 2004, University in Hagen, Department of Computer Science, 
//Database Systems for New Applications.

//SECONDO is free software; you can redistribute it and/or modify
//it under the terms of the GNU General Public License as published by
//the Free Software Foundation; either version 2 of the License, or
//(at your option) any later version.

//SECONDO is distributed in the hope that it will be useful,
//but WITHOUT ANY WARRANTY; without even the implied warranty of
//MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
//GNU General Public License for more details.

//You should have received a copy of the GNU General Public License
//along with SECONDO; if not, write to the Free Software
//Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

package viewer.update2;

import gui.SecondoObject;

import java.util.ArrayList;
import java.util.List;
import sj.lang.ListExpr;
import tools.Reporter;
import viewer.update2.InvalidRelationException;
import viewer.update2.AttributeFormatter;


/**
 *
 */
public class Tuple
{
	private String id;		
	private List<String> values;
	private RelationTypeInfo typeInfo;
	
	/**
	 * Default Constructor shall not be used.
	 **/
	private Tuple() {}

	
	public Tuple(RelationTypeInfo pTypeInfo, ListExpr pLE) throws InvalidRelationException
	{
		this.typeInfo = pTypeInfo;
		if (pTypeInfo==null || !this.readValueFromLE(pLE))
		{
			throw (new InvalidRelationException());
		}
	}
	
	/**
	 * Creates Tuple from ListExpr.
	 * If pLE is null, Tuple is empty, i.e. all values are ""
	 */
	public boolean readValueFromLE(ListExpr pLE)
	{
		boolean result = false;
		this.values = new ArrayList<String>();
		ListExpr tupleValues = pLE;
		ListExpr nextValue;
		
		// create empty Tuple
		if(pLE == null)
		{
			//Reporter.debug("Tuple.readValueFromLE: create empty Tuple ");
			for(int i=0; i<this.typeInfo.getSize(); i++)
			{				
				values.add("");
			}
			this.id = "";
			result = true;			
		}
		
		// fill Tuple with given values
		else if(tupleValues.listLength() == this.typeInfo.getSize())  // correct tuplelength
		{
			//Reporter.debug("Tuple.readValueFromLE: pLE is " + pLE.toString());
			for(int i=0; i<this.typeInfo.getSize(); i++)
			{
				nextValue = pLE.first();
				if(!this.typeInfo.get(i).Atomic)
				{
					nextValue = nextValue.rest();
					//Reporter.debug("Tuple.readValueFromLE: nextValue is " + nextValue.toString());
				}

				String val = AttributeFormatter.fromListExprToString(nextValue);
				values.add(val);
				
				int tidindex = this.typeInfo.getTidIndex();
				if (tidindex >= 0 && tidindex == i)
				{
					this.id = val.trim();
				}
				//Reporter.debug("Tuple.readValueFromLE: new value is " + val);
				
				pLE = pLE.rest();
			}
			
			if (this.getID() == null)
			{
				this.id = "";
			}
			
			result = true;
		}
		return result;
	}
	
	
	public Relation getAttributeRelation(String pAttrName) throws InvalidRelationException
	{
		HeadEntry info = this.typeInfo.get(pAttrName);
		ListExpr le = new ListExpr();
		le.readFromString("(" + info.Type + this.getValueByAttrName(pAttrName) +")");
		//Reporter.debug("Tuple.getAttributeRelation: arel le =" + le.toString());
		SecondoObject relationSO = new SecondoObject(pAttrName, le);
		Relation arel = new Relation();
		arel.readFromSecondoObject(relationSO);
		return arel;
	}

	
	public String getTypeAt(int pIndex)
	{
		if (pIndex >= 0 && pIndex < this.typeInfo.getSize())
		{
			return this.typeInfo.getAttributeType(pIndex);
		}
		return null;
	}
	
	
	public RelationTypeInfo getTypeInfo()
	{
		return this.typeInfo;
	}
	
	
	public String getValueAt(int pIndex)
	{
		if (pIndex >= 0 && pIndex < this.typeInfo.getSize())
		{
			return values.get(pIndex);
		}
		return null;
	}
	
	
	public String getValueByAttrName(String pAttrName)
	{
		int index = this.typeInfo.getAttributeNames().indexOf(pAttrName);
		return this.getValueAt(index);
	}
	
	
	public void setValueAt(String pValue, int pIndex)
	{
		if (pIndex >= 0 && pIndex < this.typeInfo.getSize())
		{
			this.values.set(pIndex, pValue);
		}
	}
	
	
	public boolean setValueByAttrName(String pValue, String pAttrName)
	{
		int index = this.typeInfo.getAttributeNames().indexOf(pAttrName);
		if (index >= 0 && index < this.typeInfo.getSize())
		{
			this.values.set(index, pValue);
			return true;
		}
		return false;
	}
	
	
	
	public String getID()
	{
		return id;
	}
	
	
	public String toString()
	{
		StringBuffer sb = new StringBuffer("[Tuple]: ");
		sb.append(", ID: ").append(this.getID());
		sb.append(", values: ");
		for (String val : this.values)
		{
			sb.append(val).append(", ");
		}
		return sb.toString();
	}
	
}