Home/ Questions/Q 653379
In Process

The Archive Base Latest Questions

Editorial Team
  • 0
Asked: 2026-05-13T22:22:33+00:00

I have an object and I want to detect what type is, so I

  • 0

I have an object and I want to detect what type is, so I can call

if (obj isa Integer)
  put(key,integerval);  
if (obj isa String)
    put(key,stringval);  
if (obj isa Boolean)
    put(key,booleanval);
Share

Leave an answer

You must login to add an answer.

Need An Account,

1 Answer

  1. Editorial Team

    You’re pretty close, actually!

    if (obj instanceof Integer)
    put(key,integerval);  
if (obj instanceof String)
    put(key,stringval);  
if (obj instanceof Boolean)
    put(key,booleanval);

    From the JLS 15.20.2:

    RelationalExpression instanceof ReferenceType

    At run time, the result of the instanceof operator is true if the value of the RelationalExpression is not null and the reference could be cast (§15.16) to the ReferenceType without raising a ClassCastException. Otherwise the result is false.

    Looking at your usage pattern, though, it looks like you may have bigger issues than this.

    • 0