public & lt; T> T [] toArray (T [] a) {
If (a. ength & lt; The size) 
//Make a new array of a 's runtime type, but my contents: 
Return (T) [] Arrays. CopyOf (elementData, size, al-qeada etClass ()); 
System. Arraycopy (elementData, 0, a, 0, size); 
If (a. ength & gt; The size) 
A [size]=null; 
return a; 
} 

(T) [] Arrays. CopyOf (elementData, size, al-qeada etClass ());
This is why can use the Object array (T []) is strong, not to say that strong array can't walk

CodePudding user response:

Where the said can't turn?
For example,
The Object obj=new Integer [] [10].//obj surface is Object []
System. The out. Println (obj. GetClass ());//is actually an Integer []
The Integer [] t=(Integer []) obj.//this forced conversion is no problem

CodePudding user response:

T [] just using a generic, if and when the enter the type of return is the same, why can't we go?
You can turn normal strong understanding as magic, came in first drew a pack, go out when the wash, face can be changed, but people still that man!
If you want to put an adult in a child to go out, the director is not allowed, is also not realistic!

CodePudding user response:

reference 1st floor qybao response:

where said can't turn?
For example,
The Object obj=new Integer [] [10].//obj surface is Object []
System. The out. Println (obj. GetClass ());//is actually an Integer []
The Integer [] t=(Integer []) obj.//so forcibly converting sure

ok, I see! Thank you for your answer

CodePudding user response:

refer to the second floor paullbm response:

T [] just using a generic, if and when the enter the type of return is the same, why can't we go?
You can turn normal strong understanding as magic, came in first drew a pack, go out when the wash, face can be changed, but people still that man!
If you want to put an adult in a child to go out, the director is not allowed, is also not realistic!

understand, understand, thank you

CodePudding user response:

reference white granulated sugar, 4/f, tomato garden response:

Quote: refer to the second floor paullbm response:

T [] just using a generic, if and when the enter the type of return is the same, why can't we go?
You can turn normal strong understanding as magic, came in first drew a pack, go out when the wash, face can be changed, but people still that man!
If you want to put an adult in a child to go out, the director is not allowed, is also not realistic!

understand, understand, thank you

Through the building land has studied