JAVA REFLECTION : java.lang.IllegalArgumentException: argument type mismatch

Question

Am using java reflection, Here am using object org.openqa.selenium.remote.RemoteWebElement, to call method called sendKeys. This method will accept characterSequence Array as a parameter type, so am passing characterSequence[] as parameter . Using classname.getMethod(sendKeys, characterSequence[]) I can get the methodname. But when this method is innvoked in runtime passing array of characterSequences[] as argument it throws

java.lang.IllegalArgumentException: argument type mismatch
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:497)
at com.thbs.manager.Reflections.callSeleniumCommand(Reflections.java:115)
at com.google.manager.Testing.doTestExecution(Testing.java:105)
at com.google.manager.Testing.main(Testing.java:22)

Could not post the entire code,but posted the code which throws error

objToCallWith = org.openqa.selenium.remote.RemoteWebElement
cls = objToCallWith.getClass();

methodName = sendKeys
params = CharSequence[].class
// send keys method accept only CharSequence[]
myMethod = cls.getMethod(methodName, params);

// able to getMethod

args = new CharSequence[]{'a','b'}
// Here Exception java.lang.IllegalArgumentException: argument type mismatch
myMethod.invoke(objToCallWith,args);

new CharSequence[]{'a','b'} is wrong. 'a' is char type and thus cannot be converted to CharSequence. You should change to new CharSequence[]{"a","b"}and it will work. — Jiyong Park
– Jiyong Park, Commented Mar 1, 2016 at 6:48
new CharSequence[]{"a","b"} is also not working showing illegal argument Exception — Sunil M M
– Sunil M M, Commented Mar 1, 2016 at 7:00

Jiyong Park · Accepted Answer · 2016-03-01 07:28:44Z

3

myMethod.invoke(objToCallWith,args);

should be changed to:

myMethod.invoke(objToCallWith, new Object[]{args});

or

myMethod.invoke(objToCallWith, (Object)args);

This is because Method.invoke is also accepting varargs arguments. So, myMethod.invoke(objToCallWith,args); is equivalent to myMethod.invoke(objToCallWith,"a", "b");, which gives two CharSqeunce objects, rather than one CharSqeuqnce[] array object.

As you might know, foo(CharSequence... args) is internally compiled as foo(CharSqeuqnce[] arg). So, when you call foo("a", "b"), it is internally foo(new CharSequence[]{"a", "b"}), with one CharSequence[] array object.

answered Mar 1, 2016 at 7:28

Jiyong Park

6743 silver badges6 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

Sunil M M Over a year ago

Error Resolved : CharSequence[]arr=CharSequence[])Array.newInstance(CharSequence.class,1); arr[0]="ab"; returnObj = myMethod.invoke(objToCallWith,new Object[]{arr});

Sunil M M · Accepted Answer · 2016-03-01 09:54:33Z

-1

CharSequence[]arr=CharSequence[])Array.newInstance(CharSequence.class,1);
arr[0]="ab";
returnObj = myMethod.invoke(objToCallWith,new Object[]{arr});

edited Mar 1, 2016 at 9:54

answered Mar 1, 2016 at 9:52

Sunil M M

871 silver badge7 bronze badges

2 Comments

rghome Over a year ago

Please add some explanation. Otherwise, it is likely to be deleted.

Johannes Jander Over a year ago

Please add some explanation. Currently, your answer is flagged "low quality" and might get removed.

Collectives™ on Stack Overflow

JAVA REFLECTION : java.lang.IllegalArgumentException: argument type mismatch

2 Answers 2

1 Comment

2 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

1 Comment

2 Comments

Your Answer

Sign up or log in

Post as a guest

Related