CSVFile.java

package FileManagement;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Iterator;

public class CSVFile {

 String fileName;
 boolean IsAsc = true;

 public CSVFile()
 {}

 /**
 * Reads the CSV file and returns array of records.
 *
 * @param file String file path to import the CSV file.
 * 
 * @return ArrayList<Record>
 * 
 */
	public ArrayList<Record> CSVReadFile(String file) throws IOException{
		ArrayList<Record> Records = new ArrayList<Record>();
		try(BufferedReader in = new BufferedReader(new FileReader(file)))
		{
			String ln;
			boolean skip_first_line = true;
			while( (ln = in.readLine()) !=null) {
				
				//skip first line - column name.
				if(skip_first_line)
				{
					skip_first_line = false;
					continue;
				}
				String row[] = ln.split(",");
			 if(row.length == 9) {

			 Records.add(new Record(
			 		Integer.parseInt(row[0]), row[1], row[2], row[3], row[4],
			 		row[5], row[6], row[7], row[8]));
			 }
			 else {
			 	Records.add(new Record(
 Integer.parseInt(row[0]), row[1], row[2], row[3], row[4],
 row[5], row[6], row[7], row[8], row[9]));
			 }
			}
			return Records;
		}


	}
	
	/**
	 * Sorts the array of records read.
	 *
	 * @param Array of records.
	 * 
	 * @return N/A
	 */

	public void sort(ArrayList<Record> Records)
	{
		 Collections.sort(Records, new Compare(this.IsAsc));
	}

	/**
	 * Prints array of record read and Sorted.
	 *
	 * @param Array of record.
	 * 
	 * @return N/A
	 * 
	 */
	public void print(ArrayList<Record> Records)
	{//iterate through record
		for(Record rec : Records){
			System.out.println(rec.id +"\t" +
							 rec.category + "\t" +
							 rec.descript +"\t" +
							 rec.dayOfTheWeek +"\t" +
							 rec.date +"\t" +
							 rec.time +"\t" +
							 rec.pdDistrict +"\t" +
							 rec.resolution +"\t" +
							 rec.address
							 );
		}
		System.out.println();
	}

	/**
	 * Sets the sort ascending order.
	 *
	 * @param Boolean value.
	 * 
	 * @return N/A
	 * 
	 */
	public void setSortDirection(boolean b)
	{
		this.IsAsc = b;
	}
	
	/**
	 * Writes the array of records to the CSV file.
	 *
	 * @param Array of record and string path to export the results.
	 * 
	 * @return N/A
	 * 
	 */

	public void save(ArrayList<Record> Records, String filePath) throws IOException{
		try(BufferedWriter out = new BufferedWriter(new FileWriter(filePath)))
		{
			out.write("IncidntNum,Category,Descript,DayOfWeek,Date,Time,PdDistrict,Resolution,Address");
			out.write("\n");
			for(Record rec : Records){

				out.write(rec.id +"," +
 							 rec.category + "," +
 							 rec.descript +"," +
 							 rec.dayOfTheWeek +"," +
 							 rec.date +"," +
 							 rec.time +"," +
 rec.pdDistrict +"," +
 rec.resolution +"," +
 rec.address
						 );
				out.write("\n");
			}
			out.close();
		}
	}

	/**
	 * Searches for string value specified in array of record.
	 *
	 * @param Array of record and string value to search.
	 * 
	 * @return ArrayList<Record>
	 * 
	 */
	
	public ArrayList<Record> search(ArrayList<Record> Records, String search_catagory)
	{
 ArrayList<Record> searchRecords = new ArrayList<Record>();
		boolean recordFound = false;
		for(Record rec : Records){
			if(rec.category.equals(search_catagory))
			{
			 // Create records to be written to the file.
 recordFound = true;
 searchRecords.add(rec);
			}
		}
		if(recordFound)
		{
			System.out.println("Records found, file generated.");
			System.out.println();
		}
		else
		{
 System.out.println("Record not found.");
		}

 return searchRecords;
	}

	/**
	 * Reads the transaction CSV file and appends the array of records to master file.
	 *
	 * @param Master file Array of records and transaction Array of records.
	 * 
	 * @return ArrayList<Record>
	 * 
	 */
	public ArrayList<Record> run_transaction(ArrayList<Record> Records_trans, ArrayList<Record> Records )
	{
		for(Record rec : Records_trans){

			if(rec.transaction.equals("insert")) {
			 //append the record
				Records.add(rec);
			}

			if(rec.transaction.equals("update")) {
				 //update the record
				Iterator<Record> i = Records.iterator();
				while (i.hasNext()){
					Record rec_temp = i.next();
					if(rec.id == rec_temp.id){
						// this is the record update
						rec_temp.category = rec.category;
						rec_temp.descript = rec.descript;
						rec_temp.dayOfTheWeek = rec.dayOfTheWeek;
						rec_temp.date = rec.date;
						rec_temp.time = rec.time;
						rec_temp.pdDistrict = rec.pdDistrict;
						rec_temp.resolution = rec.resolution;
						rec_temp.address = rec.address;
					}
				}

			}
			if(rec.transaction.equals("delete")) {

				Iterator<Record> i = Records.iterator();
				while (i.hasNext()) {
				 Record r = i.next();
				 if(rec.id == r.id){
					 i.remove();
				 }
				}

			}
		}

		return Records;
	}

}