java泛型

1，类泛型

package java.generic;public class Generic<K,V> {private K key;private V value;public Generic() {}public Generic(K key, V value) {this.key = key;this.value = value;}public K getGenenicKey() {return key;}public V getGenenicValue() {return value;}}

2，接口泛型

package java.generic;public interface GeneticInterface<GenenicA> {public GenenicA getGenenicA(GenenicA a);}

package java.generic;public class GinericClass implements GeneticInterface<String> {public String getGenenicA(String a) {return a;}}

3，方法泛型

package java.generic;public class Generic {public static <T> void outOne(T key){System.out.println(key.toString());}public static <T> void outMany(T... args) {for (T t : args) {System.out.println(t);}}public static void main() {outOne("aaaa");outOne(111);outOne(11.11);outMany("ssss", 111, 22.22);}}

4,其他用法
通配符：<?>
上下界：
<? extents T>
<? super T>
5：说明：
泛型只是java编译器的编译check，生成的java字节码会进行类型擦除，也就是说写的泛型并没有在字节码中生成，运行时动态检查。