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POJava exception handling method
 

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    <p>I'm having a little bit of trouble implementing the following method while handling the 3 exceptions I'm supposed to take care of. <strong>Should I include the try/catch blocks like I'm doing or is that to be left for the application instead of the class design</strong>?</p> <p>The method says I'm supposed to implement this:</p> <pre><code>public Catalog loadCatalog(String filename) throws FileNotFoundException, IOException, DataFormatException </code></pre> <p>This method loads the info from the archive specified in a catalog of products and returns the catalog. </p> <p>It starts by opening the file for reading. Then it proceeds to read and process each line of the file.</p> <p>The method <code>String.startsWith</code> is used to determine the type of line:</p> <ul> <li>If the type of line is "Product", the method readProduct is called.</li> <li>If the type of line is "Coffee", the method readCoffee is called.</li> <li>If the type of line is "Brewer", the method readCoffeeBrewer is called.</li> </ul> <p>After the line is processed, <code>loadCatalog</code> adds the product (product, coffee or brewer) to the catalog of products. </p> <p>When all the lines of the file have been processed, <code>loadCatalog</code> returns the Catalog of products to the method that makes the call. </p> <p>This method can throw the following exceptions:</p> <ul> <li><code>FileNotFoundException</code> — if the files specified does not exist. </li> <li><code>IOException</code> — If there is an error reading the info of the specified file. </li> <li><code>DataFormatException</code> — if a line has errors(the exception must include the line that has the wrong data)</li> </ul> <p>Here is what I have so far:</p> <pre><code>public Catalog loadCatalog(String filename) throws FileNotFoundException, IOException, DataFormatException{ String line = ""; try { BufferedReader stdIn = new BufferedReader(new FileReader("catalog.dat")); try { BufferedReader input = new BufferedReader( new FileReader(stdIn.readLine())); while(! stdIn.ready()){ line = input.readLine(); if(line.startsWith("Product")){ try { readProduct(line); } catch(DataFormatException d){ d.getMessage(); } } else if(line.startsWith("Coffee")){ try { readCoffee(line); } catch(DataFormatException d){ d.getMessage(); } } else if(line.startsWith("Brewer")){ try { readCoffeeBrewer(line); } catch(DataFormatException d){ d.getMessage(); } } } } catch (IOException io){ io.getMessage(); } }catch (FileNotFoundException f) { System.out.println(f.getMessage()); } return null; } </code></pre>
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