6.8.6 Local Variable and Parameter Names

Local variable and parameter names should be short, yet meaningful. They are often short sequences of lowercase letters that are not words. For example:

• Acronyms, that is the first letter of a series of words, as in cp for a variable holding a reference to a ColoredPoint
• Abbreviations, as in buf holding a pointer to a buffer of some kind
• Mnemonic terms, organized in some way to aid memory and understanding, typically by using a set of local variables with conventional names patterned after the names of parameters to widely used classes. For example:
  • in and out, whenever some kind of input and output are involved, patterned after the fields of java.lang.System
  • off and len, whenever an offset and length are involved, patterned after the parameters to the read and write methods of the interfaces DataInput and DataOutput of java.io

One-character local variable or parameter names should be avoided, except for temporary and looping variables, or where a variable holds an undistinguished value of a type. Conventional one-character names are:

• b for a byte
• c for a char
• d for a double
• e for an Exception
• f for a float
• i, j, and k for integers
• l for a long
• o for an Object
• s for a String
• v for an arbitrary value of some type

Local variable or parameter names that consist of only two or three uppercase letters should be avoided to avoid potential conflicts with the initial country codes and domain names that are the first component of unique package names (§7.7).

What's in a name? That which we call a rose
By any other name would smell as sweet.
—William Shakespeare, Romeo and Juliet (c. 1594), Act II, scene ii

Rose is a rose is a rose is a rose.
—Gertrude Stein, "Sacred Emily" (1913), in Geographies and Plays

. . . stat rosa pristina nomine, nomina nuda tenemus.
—Bernard of Morlay, De contemptu mundi (12th century),
quoted in Umberto Eco, The Name of the Rose (1980)