Which of the following is the recommended syntax to create a Double wrapper object with value 5.5?

easy📝 Syntax Q3 of 15

Java - Wrapper Classes

ADouble d = Double.valueOf(5.5);

BDouble d = new Double(5.5);

CDouble d = 5.5;

DDouble d = Double.parseDouble(5.5);

Step-by-Step Solution

Solution:

Step 1: Review wrapper object creation methods
Using valueOf() is the recommended way to create wrapper objects as it may cache values.
Step 2: Analyze wrapper creation options
valueOf(5.5) is the recommended static factory method as it enables caching. new Double(5.5) uses a deprecated constructor. Double d = 5.5; relies on autoboxing. Double.parseDouble(5.5) fails since it requires a String argument.
Final Answer:
Double d = Double.valueOf(5.5); -> Option A
Quick Check:
Use valueOf() to create wrapper objects = A [OK]

Quick Trick: Use valueOf() to create wrapper objects, not constructors [OK]

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