Spring MVC Beginner’s Guide

Time for action – adding an exception handler

We must show a nice error message that says that no products were found with the given product ID. Let's do that with the help of @ExceptionHandler:

1. Create a class called ProductNotFoundException under the com.packt.webstore.exception package in the source folder src/main/java. Now, add the following code to it:

   package com.packt.webstore.exception;
   
   public class ProductNotFoundException extends RuntimeException{
   
     private static final long serialVersionUID =-694354952032299587L;
   
     private String productId;
   
     public ProductNotFoundException(String productId) {
       this.productId = productId;
     }
   
     public String getProductId() {
       return productId;
     }
   
   }

2. Now, open our InMemoryProductRepository class and modify the getProductById ...