import java.util.*;
import java.util.Map.Entry;
public class ExampleWithScannerAndHashMap {
public
static void main(String[] args) {
int
count = 0;// stores the number of names
//
Scanner the reads the user input from standard input stream
Scanner
in = new Scanner(System.in);
//
Request user input till getting a valid number
System.out.println("Enter
the Number of Names U wants to display :");
while
(true) {
try
{
//
Read the user input and convert into integer
count
= in.nextInt();
//
If it is a valid number break the loop
break;
}
catch (InputMismatchException e) {
//
If it is not a valid number show the error msg
System.out.println("Please
enter a valid number : ");
}
}
in.nextLine();
// reads the enter char from buffer
//
Hashmap to store the names
Map<String,
String> hashMap = new HashMap<String, String>();
for
(int i = 1; i <= count; i++) {
System.out.println("Enter
Name " + i + " : ");
//
Add the names to hashmap with different keys
hashMap.put("name"
+ i, in.nextLine());
}
//
Print the names in the hashmap
printValues(hashMap);
System.out.println("Enter
a key to delete : ");
String
key = in.nextLine();
if
(hashMap.containsKey(key)) {
hashMap.remove(key);
System.out.println("The
element with key " + key
+
" has been removed successfully");
}
else {
System.out.println("The
entered key does not exists");
}
//Clears
the hashmap
hashMap.clear();
//
close the scanner to release the resource
in.close();
}
public
static void printValues(Map<String, String> hashMap) {
Iterator<Entry<String,
String>> iterator = hashMap.entrySet()
.iterator();
System.out.println("There
are " + hashMap.size() + " elements in HashMap. They are ");
System.out.println("Key
: Value");
while
(iterator.hasNext()) {
Entry<String,String>
entry = iterator.next();
System.out.println(entry.getKey()
+ " : "
+
entry.getValue());
}
}
}
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