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Java Collection, HashMap Exercises: Get a collection view of the values contained in this map

Java Collection, HashMap Exercises: Exercise-12 with Solution

Write a Java program to get a collection view of the values contained in this map.

Sample Solution:-

Java Code:

import java.util.*;  
public class Example12 {  
     public static void main(String args[]){  
 
  HashMap<Integer,String> hash_map= new HashMap<Integer,String>();  
    hash_map.put(1,"Red");
  hash_map.put(2,"Green");
  hash_map.put(3,"Black");
  hash_map.put(4,"White");
  hash_map.put(5,"Blue");
       
   // checking collection view of the map
   System.out.println("Collection view is: "+ hash_map.values());
 }
}

Sample Output:

Collection view is: [Red, Green, Black, White, Blue]

Java Code Editor:

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Java: Tips of the Day

Try and catch:

Java is excellent at catching errors, but it can only recover gracefully if you tell it what to do. The cascading hierarchy of attempting to perform an action in Java starts with try, falls back to catch, and ends with finally. Should the try clause fail, then catch is invoked, and in the end, there's always finally to perform some sensible action regardless of the results. Here's an example:

try {
        cmd = parser.parse(opt, args); 
       
        if(cmd.hasOption("help")) {
                HelpFormatter helper = new HelpFormatter();
                helper.printHelp("Hello ", opt);
                System.exit(0);
                }
        else {
                if(cmd.hasOption("shell") || cmd.hasOption("s")) {
                String target = cmd.getOptionValue("tgt");
                } // else
        } // fi
} catch (ParseException err) {
        System.out.println(err);
        System.exit(1);
        } //catch
        finally {
                new Hello().helloWorld(opt);
        } //finally
} //try

It's a robust system that attempts to avoid irrecoverable errors or, at least, to provide you with the option to give useful feedback to the user. Use it often, and your users will thank you!

Ref: https://red.ht/3EZc9OC