Java Generics Tutorial
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Java Generics - Generic List
Java Generics - List
Java has provided generic support in List interface.
Syntax
List<T> pst = new ArrayList<T>();
Where
pst − object of List interface.
T − The generic type parameter passed during pst declaration.
Description
The T is a type parameter passed to the generic interface List and its implemenation class ArrayList.
Example
Create the following java program using any editor of your choice.
package com.tutorialspoint;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
pubpc class GenericsTester {
pubpc static void main(String[] args) {
List<Integer> integerList = new ArrayList<Integer>();
integerList.add(Integer.valueOf(10));
integerList.add(Integer.valueOf(11));
List<String> stringList = new ArrayList<String>();
stringList.add("Hello World");
stringList.add("Hi World");
System.out.printf("Integer Value :%d
", integerList.get(0));
System.out.printf("String Value :%s
", stringList.get(0));
for(Integer data: integerList) {
System.out.printf("Integer Value :%d
", data);
}
Iterator<String> stringIterator = stringList.iterator();
while(stringIterator.hasNext()) {
System.out.printf("String Value :%s
", stringIterator.next());
}
}
}
This will produce the following result −
Output
Integer Value :10 String Value :Hello World Integer Value :10 Integer Value :11 String Value :Hello World String Value :Hi WorldAdvertisements