Why does it do this? So confuuuusing.

Operator precedence and associativity. Two points: <ul> <li>Operator <code>+</code> does string concatenation if one or both arguments are Strings.</li> <li>Operator <code>+</code> works from left to right.</li> </ul> So in your example, <code>"Hi"+6</code> is <code>"Hi6"</code>, and <code>"Hi6"+10</code> is <code>"Hi610"</code>. EDIT: As you say in a comment to another answer: If the numbers are first, then a numeric addition is done first, because the leftmost two operands are numbers. Then, only at the end, a string concatenation occurs. So that yields <code>"16Hi"</code>.

System.out.println("Hi"+6+10); prints Hi610?

1 Answers

Operator precedence and associativity.

Two points:

Operator + does string concatenation if one or both arguments are Strings.
Operator + works from left to right.

So in your example, "Hi"+6 is "Hi6", and "Hi6"+10 is "Hi610".

EDIT: As you say in a comment to another answer: If the numbers are first, then a numeric addition is done first, because the leftmost two operands are numbers. Then, only at the end, a string concatenation occurs. So that yields "16Hi".