java - Owned One-to-Many Relationships -

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मेरे पास दो वर्ग हैं: 

  सार्वजनिक वर्ग कुत्ता {@PrimaryKey @Persistent (valueStrategy = IdGeneratorStrategy.IDENTITY) निजी कुंजी कुंजी; @ परसिस्टेंट (मैप किया हुआ = "कुत्ता") @ एलेमेंट (आश्रित = "सच") निजी सूची & gt; खिलौना & gt; खिलौने; } सार्वजनिक वर्ग की खिलौना {@PrimaryKey @ परसिस्टेंट (मान स्ट्रेटजी = आईडीजनरेटर। श्रेय।) निजी कुंजी; @ प्रस्तुति निजी नाम का नाम; @ प्राइसेन्ट निजी कुत्ते का कुत्ता; }   
 1) अगर मैं यह करता हूं  
  खिलौना खिलौना = नया खिलौना (); toy.setDog (कुत्ता); // कुत्ता एक कुत्ता वर्ग pm.makePersistent (खिलौना) है;   
 क्या मैं इस खिलौना को getToys के माध्यम से कुत्ते से प्राप्त कर सकता हूं?  
 2) अगर मैं यह दो बार करता हूं  
  खिलौना खिलौना = नया खिलौना (); toy.setName ( "एएए"); toy.setDog (कुत्ता); pm.makePersistent (खिलौना);   
 क्या दैटस्टोर में दो बिल्कुल समान खिलौने दोहराएंगे? 
 धन्यवाद! 
   
 
 
     
  1.  
     यदि आप "toy.setDog" करते हैं तो आप खिलौने को खिलौनों में नहीं जोड़ चुके हैं खिलौने की सूची ... यानी संबंध द्विदिश है और आपको दोनों को सेट करना होगा पक्षों।   
  2.  
     क्या बिल्कुल खिलौने? यदि आप 2 खिलौने जोड़ते हैं तो आपके पास 2 खिलौने हैं। उनके क्षेत्रों के मूल्य अप्रासंगिक हैं, केवल पहचान के मामलों।

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