/*	DBFWriter	Class for defining a DBF structure and addin data to that structure and 	finally writing it to an OutputStream.	This file is part of JavaDBF packege.	author: anil@linuxense.com	license: LGPL (http://www.gnu.org/copyleft/lesser.html)	$Id: DBFWriter.java,v 1.9 2004/03/31 10:57:16 anil Exp $*/package com.linuxense.javadbf;import java.io.*;import java.util.*;/**	An object of this class can create a DBF file.	Create an object, <br>	then define fields by creating DBFField objects and<br>	add them to the DBFWriter object<br>	add records using the addRecord() method and then<br>	call write() method.*/public class DBFWriter extends DBFBase {	/* other class variables */	DBFHeader header;	Vector v_records = new Vector();	int recordCount = 0;	RandomAccessFile raf = null; /* Open and append records to an existing DBF */	boolean appendMode = false;	/**		Creates an empty Object.	*/	public DBFWriter() {		this.header = new DBFHeader();	}	/**	 	Creates a DBFWriter which can append to records to an existing DBF file.		@param dbfFile. The file passed in shouls be a valid DBF file.		@exception Throws DBFException if the passed in file does exist but not a valid DBF file, or if an IO error occurs.	 */	public DBFWriter( File dbfFile) 	throws DBFException {		try {			this.raf = new RandomAccessFile( dbfFile, "rw");			/* before proceeding check whether the passed in File object 			 is an empty/non-existent file or not.			 */			if( !dbfFile.exists() || dbfFile.length() == 0) {				this.header = new DBFHeader();				return;			}			header = new DBFHeader();			this.header.read( raf);			/* position file pointer at the end of the raf */			this.raf.seek( this.raf.length()-1 /* to ignore the END_OF_DATA byte at EoF */);		}		catch( FileNotFoundException e) {			throw new DBFException( "Specified file is not found. " + e.getMessage());		}		catch( IOException e) {			throw new DBFException( e.getMessage() + " while reading header");		}		this.recordCount = this.header.numberOfRecords;	}	/**		Sets fields.	*/	public void setFields( DBFField[] fields)	throws DBFException {		if( this.header.fieldArray != null) {			throw new DBFException( "Fields has already been set");		}		if( fields == null || fields.length == 0) {			throw new DBFException( "Should have at least one field");		}		for( int i=0; i<fields.length; i++) {			if( fields[i] == null) {				throw new DBFException( "Field " + (i+1) + " is null");			}		}		this.header.fieldArray = fields;		try {			if( this.raf != null && this.raf.length() == 0) {				/* 			  	this is a new/non-existent file. So write header before proceeding		 		*/				this.header.write( this.raf);			}		}		catch( IOException e) {			throw new DBFException( "Error accesing file");		}	}	/**		Add a record.	*/	public void addRecord( Object[] values)	throws DBFException {		if( this.header.fieldArray == null) {			throw new DBFException( "Fields should be set before adding records");		}		if( values == null) {			throw new DBFException( "Null cannot be added as row");		}		if( values.length != this.header.fieldArray.length) {			throw new DBFException( "Invalid record. Invalid number of fields in row");		}		for( int i=0; i<this.header.fieldArray.length; i++) {			if( values[i] == null) {				continue;			}			switch( this.header.fieldArray[i].getDataType()) {				case 'C':					if( !(values[i] instanceof String)) {						throw new DBFException( "Invalid value for field " + i);					}					break;				case 'L':					if( !( values[i] instanceof Boolean)) {					  throw new DBFException( "Invalid value for field " + i);					}					break;				case 'N':					if( !( values[i] instanceof Double)) {						throw new DBFException( "Invalid value for field " + i);					}					break;				case 'D':					if( !( values[i] instanceof Date)) {						throw new DBFException( "Invalid value for field " + i);					}					break;				case 'F':					if( !(values[i] instanceof Double)) {						throw new DBFException( "Invalid value for field " + i);					}					break;			}		}		if( this.raf == null) {			v_records.addElement( values);		}		else {			try {							writeRecord( this.raf, values);				this.recordCount++;			}			catch( IOException e) {				throw new DBFException( "Error occured while writing record. " + e.getMessage());			}		}	}	/**		Writes the set data to the OutputStream.	*/	public void write( OutputStream out)	throws DBFException {		try {			if( this.raf == null) {				DataOutputStream outStream = new DataOutputStream( out);				this.header.numberOfRecords = v_records.size();				this.header.write( outStream);				/* Now write all the records */				int t_recCount = v_records.size();				for( int i=0; i<t_recCount; i++) { /* iterate through records */					Object[] t_values = (Object[])v_records.elementAt( i);					writeRecord( outStream, t_values);				}				outStream.write( END_OF_DATA);				outStream.flush();			}			else {				/* everything is written already. just update the header for record count and the END_OF_DATA mark */				this.header.numberOfRecords = this.recordCount;				this.raf.seek( 0);				this.header.write( this.raf);				this.raf.seek( raf.length());				this.raf.writeByte( END_OF_DATA);				this.raf.close();			}		}		catch( IOException e) {			throw new DBFException( e.getMessage());		}	}	public void write()	throws DBFException {		this.write( null);	}	private void writeRecord( DataOutput dataOutput, Object []objectArray) 	throws IOException {		dataOutput.write( (byte)' ');		for( int j=0; j<this.header.fieldArray.length; j++) { /* iterate throught fields */			switch( this.header.fieldArray[j].getDataType()) {				case 'C':					if( objectArray[j] != null) {						String str_value = objectArray[j].toString();							dataOutput.write( Utils.textPadding( str_value, characterSetName, this.header.fieldArray[j].getFieldLength()));					}					else {						dataOutput.write( Utils.textPadding( "", this.characterSetName, this.header.fieldArray[j].getFieldLength()));					}					break;				case 'D':					if( objectArray[j] != null) {						GregorianCalendar calendar = new GregorianCalendar();						calendar.setTime( (Date)objectArray[j]);						StringBuffer t_sb = new StringBuffer();						dataOutput.write( String.valueOf( calendar.get( Calendar.YEAR)).getBytes());						dataOutput.write( Utils.textPadding( String.valueOf( calendar.get( Calendar.MONTH)+1), this.characterSetName, 2, Utils.ALIGN_RIGHT, (byte)'0'));						dataOutput.write( Utils.textPadding( String.valueOf( calendar.get( Calendar.DAY_OF_MONTH)), this.characterSetName, 2, Utils.ALIGN_RIGHT, (byte)'0'));					}					else {						dataOutput.write( "        ".getBytes());					}					break;				case 'F':					if( objectArray[j] != null) {						dataOutput.write( Utils.doubleFormating( (Double)objectArray[j], this.characterSetName, this.header.fieldArray[j].getFieldLength(), this.header.fieldArray[j].getDecimalCount()));					}					else {						dataOutput.write( Utils.textPadding( "?", this.characterSetName, this.header.fieldArray[j].getFieldLength(), Utils.ALIGN_RIGHT));					}					break;				case 'N':					if( objectArray[j] != null) {						dataOutput.write(							Utils.doubleFormating( (Double)objectArray[j], this.characterSetName, this.header.fieldArray[j].getFieldLength(), this.header.fieldArray[j].getDecimalCount()));					}					else {						dataOutput.write( 							Utils.textPadding( "?", this.characterSetName, this.header.fieldArray[j].getFieldLength(), Utils.ALIGN_RIGHT));					}					break;				case 'L':					if( objectArray[j] != null) {						if( (Boolean)objectArray[j] == Boolean.TRUE) {							dataOutput.write( (byte)'T');						}						else {							dataOutput.write((byte)'F');						}					}					else {						dataOutput.write( (byte)'?');					}					break;				case 'M':					break;				default:						throw new DBFException( "Unknown field type " + this.header.fieldArray[j].getDataType());			}		}	/* iterating through the fields */	}}