GenericsJ2SE 1.4 ã§æ›¸ã„ãŸã‚„ã‚ŠãŸã„ã“㨠Class fooClass = Class.forName("Foo"); Foo fooObject = (Foo)fooClass.newInstance(); ã“れを generics を使ã£ã¦ã‚¹ãƒžãƒ¼ãƒˆã«æ›¸ããŸã„． 案1 Class<Foo> fooClass = (Class<Foo>)Class.forName("Foo"); Foo fooObject = fooClass.newInstance(); ã‚ャストãŒå…¥ã£ã¦ã„る時点㧠generics をスマートã«ä½¿ã£ã¦ã„ãªã„． 案2 Class<?> fooClass = Class.forName("Foo"); Foo fooObject = fooClass.newInstance(); コンパイルエラー．? 㨠Foo ã¯äº’æ›ã˜ã‚ƒãªã„． ã§ç…®è©°ã¾ã£ã¦æ¤œç´¢ã—ã¦ã¿ãŸã¨ã“ã‚
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