Vertical Whitespace

• A single blank line should be used to separate…
• Package declaration
• Class declarations
• Constructors
• Methods
• Static initializers
• Instance initializers
• …and may be used to separate logical groups of
• import statements
• fields
• statements
• Multiple consecutive blank lines should only be used to separate groups of related members and not as the standard inter-member spacing.

Horizontal Whitespace

• A single space should be used…
• To separate keywords from neighboring opening or closing brackets and braces
• Before and after all binary operators and operator like symbols such as arrows in lambda expressions and the colon in enhanced for loops (but not before the colon of a label)
• After // that starts a comment.
• After commas separating arguments and semicolons separating the parts of a for loop.
• After the closing parenthesis of a cast.
• In variable declarations it is not recommended to align types and variables.