How can I know if Object is String type object

Question

I have to know if Object is String or any other class type  how can I do it  Currently I do it like below  but its not very good coding   try       String myString    String  object         do stuff here   catch Exception e           it wasn t string  so just continue

User · Answer

From JDK 14  which includes JEP 305 we can do Pattern Matching for instanceof  Patterns basically test that a value has a certain type  and can extract information from the value when it has the matching type    Before Java 14  if  obj instanceof String        String str    String  obj     need to declare and cast again the object        str contains         else       str            Java 14 enhancements  if    obj instanceof String str            str contains           no need to declare str object again with casting   else          str         We can also combine the type check and other conditions together  if  obj instanceof String str  amp  amp  str length    gt  4      str contains           The use of pattern matching in instanceof should reduce the overall number of explicit casts in Java programs   PS  instanceOf will only match when the object is not null  then only it can be assigned to str

User · Answer

javamonkey79 is right  But don t forget what you might want to do  e g  try something else or notify someone  if object is not an instance of String    String myString  if  object instanceof String      myString    String  object    else        do something else          BTW  If you use ClassCastException instead of Exception in your code above  you can be sure that you will catch the exception caused by casting object to String   And not any other exceptions caused by other code  e g  NullPointerExceptions

User · Answer

Could you not use typeof object  to compare against

User · Answer

Its possible you don t need to know depending on what you are doing with it   String myString   object toString      or if object can be null  String myString   String valueOf object

User · Answer

Guard your cast with instanceof  String myString  if  object instanceof String      myString    String  object

User · Answer

Use the instanceof syntax   Like so   Object foo        if  foo instanceof String          do something String related to foo

User · Answer

object instanceof Type   is true if the object is a Type or a subclass of Type   object getClass   equals Type class     is true only if the object is a Type

User · Answer

Either use instanceof or method Class isAssignableFrom Class lt   gt  cls

[java] How can I know if Object is String type object?

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