Java Generics Tutorial
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- Java Generics - No Static field
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- Java Generics - Generic Map
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- Bounded Type Parameters
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- Java Generics - Multiple Type
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- Java Generics - Generic Classes
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- Java Generics - Overview
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Java Generics - No Static field
Java Generics - No Static field
Using generics, type parameters are not allowed to be static. As static variable is shared among object so compiler can not determine which type to used. Consider the following example if static type parameters were allowed.
Example
package com.tutorialspoint; pubpc class GenericsTester { pubpc static void main(String[] args) { Box<Integer> integerBox = new Box<Integer>(); Box<String> stringBox = new Box<String>(); integerBox.add(new Integer(10)); printBox(integerBox); } private static void printBox(Box box) { System.out.println("Value: " + box.get()); } } class Box<T> { //compiler error private static T t; pubpc void add(T t) { this.t = t; } pubpc T get() { return t; } }
As stringBox and integerBox both have a stared static type variable, its type can not be determined. Hence static type parameters are not allowed.
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