Kotlin Vs Java

Some Java issues addressed in Kotlin

Kotlin fixes a series of issues that Java suffers from

• Null references are controlled by the type system
• Arrays in Kotlin are invariant
• Kotlin has proper function types, as opposed to Java's SAM-conversions
• Use-site variance

What Java has that Kotlin does not

• Checked exceptions that are not classes
• Static members
• Wildcard-types

What Kotlin has that Java does not

• Lambda expressions + Inline functions
• Null-safety
• String templates
• Primary constructors
• Type inference for variable and property types
• Declaration-site variance & Type projections
• Operator overloading
• Companion objects
• Separate interfaces for read-only and mutable collections