Confusing question on classpath please help

[Apratim Khandalkar]

Hi ,

Following is the question at the end of chapter10 from k&B book

Given the default classpath:
/foo
And this directory structure:
foo
|
test
|
xcom
|--A.class
|--B.java
And these two files:
package xcom;
public class A { }
package xcom;
public class B extends A { }

Which allows B.java to compile? (Choose all that apply.)
A. Set the current directory to xcom then invoke
javac B.java
B. Set the current directory to xcom then invoke
javac -classpath . B.java
C. Set the current directory to test then invoke
javac -classpath . xcom/B.java
D. Set the current directory to test then invoke
javac -classpath xcom B.java
E. Set the current directory to test then invoke
javac -classpath xcom:. B.java

and correct answer given is C .This is confusing to me why B can't be correct answer.Please help

[Robert Elbourn]

B cannot be the correct answer because the "javac" command doesn't looks for "/xcom/B.java", its looking for "/B.java" so you need to state it!
This bit "-classpath ." is used for the .class files (not the java)and works ok!
hence you need to qualify the B.java name by prefixing its direct directory xcom.

hope that makes sense!

[Prav sharma]

Hi Robert.

Even if we assume that your statement that the Java file will be searched in the root directory. I am confused that how come the A.class will be found in this scenario. The classpath has been set to current directory and that means that we are in Test directory not in XCOM directory where A.class file is actually present.
How come option "C" is correct ???