java - What is difference between Vector and Linked List? -

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इस सवाल का पहले से ही एक उत्तर है: < / पी>

  • 16 उत्तर

क्यों Primitives के लिए समर्थन है डेटा प्रकार जब जावा में सब कुछ वस्तु है हालांकि जावा सभी प्राइमटाइव्स डेटा प्रकार के रैपर वर्ग प्रदान करता है

हम प्राथमिकताएं का उपयोग करते हैं क्योंकि वे तेज़ हैं .. यहां त्वरित संदर्भ के लिए पोस्ट से जवाब दिया गया है

यहोशू ब्लॉच के में, आइटम 5: "अनावश्यक वस्तुओं को बनाने से बचें", वह निम्नलिखित कोड उदाहरण पोस्ट करता है: 

  सार्वजनिक स्थिर शून्य मुख्य (स्ट्रिंग [] आर्ग्स) {लंबी राशि = 0 एल; // लम्बा, लंबे समय तक नहीं (लंबे समय के लिए = 0; i & lt; = पूर्णांक.एमएक्स_एव्वान; i ++) {sum + =; } System.out.println (sum); }

और इसे चलाने के लिए 43 सेकंड लगते हैं। आदिम में लांग को लेकर इसे 6.8 सेकंड तक लाया जाता है ... यदि यह कोई संकेत है कि हम प्राथमिकताओं का उपयोग क्यों करते हैं।

मूल मूल्य समानता की कमी भी एक चिंता ( .equals () < / Code> biziclop के लिए == की तुलना में काफी शब्दबध्द है): 

  वर्ग biziclop {सार्वजनिक स्थिर शून्य मुख्य (स्ट्रिंग [] args ) {System.out.println (नई पूर्णांक (5) == नई पूर्णांक (5)); System.out.println (नई पूर्णांक (500) == नई पूर्णांक (500)); System.out.println (पूर्णांक.वल्यूउफ़ (5) == पूर्णांक.वल्यूओफ़ (5)); System.out.println (पूर्णांक.वल्यूओफ़ (500) == पूर्णांक.वल्यूओफ़ (500)); }}

में परिणाम: 

  सी: \ दस्तावेज़ और सेटिंग्स \ चमक \ मेरे दस्तावेज़ & gt; जावा biziclop false false true false

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