2Dot grammar

http://www.cnblogs.com/mjios/archive/2013/04/08/3006577.html

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#import <Foundation/Foundation.h>
#import "Student.h"

int main(int argc, const char * argv[])
{
    @autoreleasepool {
        Student *stu = [[Student alloc] init];

        // 设置age的值
        [stu setAge:];

        // 取出age的值
        int age = [stu age];

        NSLog(@"age is %i", age);

        [stu release];
    }
    return ;
}

用点语法如何表示？