编译参数化构造函数代码期间的Eclipse错误

Question

When I write a simple parametrised constructor program, it compiles and runs in the command line.

However when it is executed within the Eclipse IDE, I received the following exception:

Exception in thread "main" java.lang.NoSuchMethodError: a_constructor.Test.(II)V at a_constructor.ParametrizedConstructor.main(ParametrizedConstructor.java:15).

Code :

//write a java program which listed the concept of parameterized constructor
class Test {
    int a,b;
    Test (int x, int y) {
        a=x;
        b=y;
        System.out.println("========================");
        System.out.println("value of a=" +a);
        System.out.println("value of b=" +b);
        System.out.println("========================");
    }
}
public class ParametrizedConstructor {
    public static void main(String[] args) {
        Test t1=new Test(10,20);
        Test t2=new Test(100,200);
        Test t3=new Test(1000,2000);
    }
}

Answer 1

The ParametrizedConstructor code is clean and doesn't have any issues.

Try:

• Delete the class files which were generated using the command prompt - If you are using the same location through eclipse to compile the same file.
• Make sure the Java Compiler and Java Build path was matched with the JDK versions.

Alternate Solutions:

• Try placing the code in Eclipse > Java Project > Under default package and run the file.
• We need to have the make sure that the compilation unit is matched to the class name ParametrizedConstructor.java (ie., public class)

For References - Check also the below links for better understanding:

• Possible Causes of 'java.lang.NoSuchMethodError: main Exception in thread "main"'