Java scriptten anlayan arkadaşlar

/*< date datetime *******************************************************************/ 
  fValidate.prototype.date = function( formatStr, delim, code, specDate ) 
  { 
  	if ( this.typeMismatch( 'text' ) ) return; 
  	if ( typeof formatStr == 'undefined' ) 
  	{ 
  		this.paramError( 'formatStr' ); 
  		return; 
  	} 
   
  	delim = this.setArg( delim, "/" ); 
   
  	var error	= [this.elem.fName, formatStr.replace( /\//g, delim )]; 
  	var format  = formatStr.split( "/" ); 
  	var compare = this.elem.value.split( delim ); 
  	var order   = new Object(); 
  	 
  	for ( var i = 0; i < format.length; i++ ) 
  	{ 
  		switch( format[i].charAt( 0 ).toLowerCase() ) 
  		{ 
  			case 'm' : 
  				order.months = i; 
  				break; 
  			case 'd' : 
  				order.days = i; 
  				break; 
  			case 'y' : 
  				order.years = i; 
  				break; 
  		} 
  	} 
  	var thisDate = new Date( compare[order.years], compare[order.months]-1, compare[order.days] ); 
  	 
  	if ( isNaN( thisDate ) || thisDate.getDate() != compare[order.days] || thisDate.getMonth() != compare[order.months]-1 || thisDate.getFullYear().toString().length != formatStr.match( /y/g ).length ) 
  	{ 
  		this.throwError( error ); 
  		return; 
  	} 
  	 
  	var compareElem = this.form.elements[specDate]; 
  	if ( typeof compareElem != 'undefined' ) 
  	{ 
  		specDate = compareElem.validDate || compareElem.value; 
  	} 
  	var compareDate = ( specDate == 'today' )? 
  		new Date(): 
  		new Date( specDate ); 
  	compareDate.setHours(0); 
  	compareDate.setMinutes(0); 
  	compareDate.setSeconds(0); 
  	compareDate.setMilliseconds(0); 
  	 
  	var timeDiff = compareDate.getTime() - thisDate.getTime(); 
  	var dateOk   = false; 
  	 
  	switch ( parseInt( code ) ) { 
  		case 1 :	// Before specDate 
  			dateOk	= Boolean( timeDiff > 0 ); 
  			error	= 1; 
  			break; 
  		case 2 :	// Before or on specDate 
  			dateOk	= Boolean( ( timeDiff + 86400000 ) > 0 ); 
  			error	= 2; 
  			break; 
  		case 3 :	// After specDate 
  			dateOk	= Boolean( timeDiff < 0 ); 
  			error	= 3; 
  			break; 
  		case 4 :	// After or on specDate 
  			dateOk	= Boolean( ( timeDiff - 86400000 ) < 0 ); 
  			error	= 4; 
  			break; 
  		default : dateOk = true; 
  		} 
  	if ( !dateOk ) 
  	{ 
  		this.throwError( [specDate], error ); 
  	} 
  	this.elem.validDate = thisDate.toString(); 
  }	 
  /*/>*/