Java Package Names Cannot Start with Numbers | Generated by AI
In Java, a package name cannot start with a number. According to the Java Naming Conventions and the Java Language Specification:
- Package names must be valid identifiers.
- A valid identifier in Java must start with a letter (A-Z or a-z), an underscore (
_), or a dollar sign ($). - Numbers (0-9) are allowed in identifiers, but only after the first character.
For example:
- Valid package names:
com.example,my_package,a123 - Invalid package names:
123example,1package
If you try to use a package name starting with a number, the Java compiler will throw a syntax error. To work around this, you can:
- Start the package name with a letter or underscore, e.g.,
a123.exampleor_123.example. - Use a descriptive name that follows conventions, like
com.example.project123.
This rule ensures consistency and compatibility across Java’s naming system.