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In the absence of autoboxing, the values of boxed primitives cannot be compared using the == and != operators by default. This is because these are interpreted as reference comparison operators. This condition is demonstrated in the first noncompliant code example.

Wiki MarkupAutoboxing on the other hand, can also produce subtle effects. It works by automatically wrapping the primitive type to the corresponding wrapper object. Some care should be taken during this process, especially when performing comparisons. The Java Language Specification \[[JLS 2005|AA. Bibliography#JLS 05]\] explains this point Specification Section 5.1.7 Boxing Conversion explains this point clearly:

If the value p being boxed is true, false, a byte, a char in the range \u0000 to \u007f, or an int or short number between -128 and 127, then let r1 and r2 be the results of any two boxing conversions of p. It is always the case that r1 == r2.

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\[[Bloch 2009|AA. Bibliography#Bloch 09]\] 4. "Searching for the One"
\[[JLS 2005|AA. Bibliography#JLS 05]\] Section 5.1.7, "Boxing Conversion"
\[[Pugh 2009|AA. Bibliography#Pugh 09]\] Using == to compare objects rather than .equals

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