filecatalogloader.java

来自「SSD3 实验5的上交文件 自己实验做得」· Java 代码 · 共 92 行

import java.util.*;
import java.io.*;

public class FileCatalogLoader implements  CatalogLoader{
	public Catalog loadCatalog(String filename)throws FileNotFoundException,IOException,DataFormatException{
		Catalog catalog = new Catalog();
		BufferedReader reader = new BufferedReader(new FileReader(filename));
		String line = reader.readLine();
		
		while(line != null)
		{ 
			Product product = null;
			if(line.startsWith("Product")){
				product = readProduct(line);
			} else if(line.startsWith("Coffee")){
				product = readCoffee(line);
			} else if(line.startsWith("Brewer")){
				product = readCoffeeBrewer(line);
			} else {
				throw new DataFormatException(line);
			}
			
			catalog.addProduct(product);
			
			line = reader.readLine();	
		}
		
		    reader.close();
		    
		    return catalog;
			
	    }
	
	private Product readProduct(String line)throws DataFormatException{
		StringTokenizer toKenizer = new StringTokenizer(line,"_");
		
		if(toKenizer.countTokens() != 4){
			throw new DataFormatException(line);
		} else {
			try{
				String prefix = toKenizer.nextToken();
				
			    return new Product (toKenizer.nextToken(),
						toKenizer.nextToken(),Double.parseDouble(toKenizer.nextToken()));
			} catch (NumberFormatException  nfe) {
				throw new DataFormatException(line);
			}
		}
			
	}
	
	
	private Coffee readCoffee(String line) throws DataFormatException{
		StringTokenizer toKenizer = new StringTokenizer(line,"_");
		
		if(toKenizer.countTokens() != 10){
			throw new DataFormatException(line);
		} else {
			try{
				String prefix = toKenizer.nextToken();
				
			    return new Coffee (toKenizer.nextToken(),
						toKenizer.nextToken(),Double.parseDouble(toKenizer.nextToken()),toKenizer.nextToken(),toKenizer.nextToken()
						,toKenizer.nextToken(),toKenizer.nextToken(),toKenizer.nextToken(),toKenizer.nextToken());
			} catch (NumberFormatException  nfe) {
				throw new DataFormatException(line);
			}
		}
	}
	
	
	private CoffeeBrewer readCoffeeBrewer(String line) throws DataFormatException {
		StringTokenizer toKenizer = new StringTokenizer(line,"_");
		
		if(toKenizer.countTokens() != 7){
			throw new DataFormatException(line);
		} else {
			try{
				String prefix = toKenizer.nextToken();
				
			    return new CoffeeBrewer (toKenizer.nextToken(),
						toKenizer.nextToken(),Double.parseDouble(toKenizer.nextToken()),toKenizer.nextToken(),toKenizer.nextToken()
						,Integer.parseInt(toKenizer.nextToken()));
			} catch (NumberFormatException  nfe) {
				throw new DataFormatException(line);
			}
		}
	}

}