- You must spell things correctly, or at least consistently.
- Java is a class-based language where everything is defined within a class, and the class name must match the file name.
- The Main Method controls the program's actions.
- System.out
generates output to the console.
- System.out.print()
displays text and keeps the cursor on the same line.
- System.out.println()
displays text and moves the cursor to the next line.
- A string literal is a sequence of characters enclosed in double quotes (e.g., "This is a string literal."
).
- Syntax errors, such as missing semicolons, prevent the program from compiling.
- Logic errors occur when the program runs but produces incorrect results due to faulty reasoning.
- A type defines a set of values and operations on them.
- Data types can be primitive (e.g., int
, boolean
, double
) or reference types.
- Variables consist of letters, digits, or underscores and are case-sensitive.
- Variable names cannot start with a digit or use spaces or special characters.
- Use camel case for variable names (e.g., myVariable
).
- A literal represents a fixed value (e.g., numbers, characters).
- Arithmetic operations include +
, -
, *
, /
, and %
(modulus).
- Operator precedence determines the order of arithmetic operations. Parentheses take precedence over *
, /
, %
, followed by +
and -
.
- Compound assignment operators include +=
, -=
, *=
, /=
, %=
.
- Increment (++
) and decrement (--
) operators add or subtract 1 from a variable.
- Division with integers truncates the decimal part. Use double
to get a floating-point result.
- Integer.MAX_VALUE
and Integer.MIN_VALUE
represent the largest and smallest possible integer values.