Length limit for a variable name in Java [duplicate]

Answer 1

No one in their right mind should ever come within miles of the limit. You reach a point where it defeats the purpose. You want to choose names that clarify your intent, but that doesn't mean a variable name should rival "Ulysses" in length. The limit has more to do with good taste and readability.

Answer 2

Given that a java.lang.String has a field

private final int count;

to specify the number of characters in it, the maximum identifier length must be no more than

Integer.MAX_VALUE

Answer 3

According to the class file format spec (under section 4.11):

The length of field and method names, field and method descriptors, and other constant string values is limited to 65535 characters by the 16-bit unsigned length item of the CONSTANT_Utf8_info structure (§4.4.7). Note that the limit is on the number of bytes in the encoding and not on the number of encoded characters. UTF-8 encodes some characters using two or three bytes. Thus, strings incorporating multibyte characters are further constrained.

This applies to local variables as well because of the LocalVariableTable pointing to CONSTANT_Utf8_info values for the variable names.