Applied through KForce for a contractual position.

The interview was conducted by the Developmental Manager and an Engineer.

They were looking for very strong Java, RDBMS, and AWS skills, as the project I was moving to was focused on Data Analytics and Data Migration.

1. Asked to write my own REST services with Spring Boot and was subsequently asked to write a JUnit test for it.

2. Write a "group by" operation in Java.

Assume there is a CSV file called "emp_dept.txt". The file has two columns, "employee_id" and "dept_id", separated by a comma. Write the equivalent of the following SQL query: sql SELECT dept_id, COUNT() FROM table1 WHERE dept_id != 3 GROUP BY dept_id HAVING COUNT() > 50 ORDER BY COUNT(*) DESC

First, explain the query, and then implement it in Java without using any ORM/JPA.

1. Consider the following program:

java public class ProgramGenerator { public static class Expression { private int lhs; public int getLhs() { return lhs; } public void setLhs(int lhs) { this.lhs = lhs; }

    private int rhs;
    public int getRhs() { return rhs; }
    public void setRhs(int rhs) { this.rhs = rhs; }

    private String operator;
    public String getOperator() { return operator; }
    public void setOperator(String operator) { this.operator = operator; }
}

public static void generateProgram(ProgramGenerator.Expression expression) {
    System.out.println("public class ConstructedProgram {");
    System.out.println("public static void main(String[] args) {");
    System.out.print("System.out.println(");
    System.out.print(expression.getLhs());
    System.out.print(expression.getLhs() == 7 ? "-" : expression.getOperator());
    System.out.print(expression.getLhs() == 7 ? expression.getRhs() * 2 : expression.getRhs());
    System.out.println(");");
    System.out.println("}\n}");
}

// ... other methods may exist here

}

What is the output of the following code snippet:

java ProgramGenerator.Expression expression = new ProgramGenerator.Expression(); expression.setLhs(7); expression.setRhs(5); expression.setOperator("+"); ProgramGenerator.generateProgram(expression);

a) Modify the ProgramGenerator class so that if lhs is 7, the expression is changed such that the operator is inverted (i.e., '+' becomes '-' and '-' becomes '+') and the rhs is multiplied by two. In the above example, the output of ConstructedProgram will be -3.