using predefined class name String in my project

Question

I have the below code which throws the error given below. when the 'String[] args' is replaced with 'java.lang.String[] args' it doesn't throw error and runs method s1.method1().

Problem: why is the local String given preference over java.lang.String ? according delegation model the Bootstrap class loader gets preference and java.lang.String loaded before the Test class is loaded. Am I missing something here. please point me to any reference for this behavior.

Test.java:

package diff;
class String {

    public void method1(){
    System.out.println("in my method");
    }
}

class Test {
    public static void main(String[] args){
        String s1 = new String();
        s1.method1();
    }
}

Error: Main method not found in class diff.Test, please define the main method as: public static void main(String[] args) or a JavaFX application class must extend javafx.application.Application

Answer 1

Problem: why is the local String given preference over java.lang.String ?

The local name masks the one in java.lang. The java.lang package is implicitly imported by the compiler for every program, however you can't use java.lang.String as String because you masked the name String. As you noted, you can use java.lang.String or rename your String class (in short, don't add custom classes that conflict with class names from java.lang). This is not a class-loader issue, as after compilation all classes are fully qualified in the byte code.