泛型

泛型

泛型类

修饰符 class 类名<类型> { }

public class Generic<T> {
    private T t;
    public T getT() {
        return t;
}
    public void setT(T t) {
        this.t = t;
        }
}

public class GenericDemo {
    public static void main(String[] args) {
        Generic<String> g1 = new Generic<String>();
        g1.setT("林青霞");
        System.out.println(g1.getT());
        Generic<Integer> g2 = new Generic<Integer>();
        g2.setT(30);
        System.out.println(g2.getT());
        Generic<Boolean> g3 = new Generic<Boolean>();
        g3.setT(true);
        System.out.println(g3.getT());
	}
}

泛型方法

修饰符 <类型> 返回值类型 方法名(类型 变量名) { }

public class Generic {
    public <T> void show(T t) {
        System.out.println(t);
    }
}

public class GenericDemo {
    public static void main(String[] args) {
        Generic g = new Generic();
        g.show("林青霞");
        g.show(30);
        g.show(true);
        g.show(12.34);
    }
}

泛型接口

修饰符 interface 接口名<类型> { }

public interface Generic<T> {
	void show(T t);
}

public class GenericImpl<T> implements Generic<T> {
    @Override
    public void show(T t) {
    	System.out.println(t);
    }
}

public class GenericDemo {
    public static void main(String[] args) {
        Generic<String> g1 = new GenericImpl<String>();
        g1.show("林青霞");
        Generic<Integer> g2 = new GenericImpl<Integer>();
        g2.show(30);
    }
}