### Question:
DefaultProblem implements Problem { public int getColumnNumber() { return columnNumber; } DefaultProblem( String message, Severity severity, String source, int lineNumber, int columnNumber,
                                   Exception exception ); String getSource(); int getLineNumber(); int getColumnNumber(); String getLocation(); Exception getException(); String getMessage(); Severity getSeverity(); @Override String toString();  }### Answer:
@Test public void testGetColumnNumber() { DefaultProblem problem = new DefaultProblem( null, null, null, -1, -1, null ); assertEquals( -1, problem.getColumnNumber() ); problem = new DefaultProblem( null, null, null, -1, 42, null ); assertEquals( 42, problem.getColumnNumber() ); problem = new DefaultProblem( null, null, null, -1, Integer.MAX_VALUE, null ); assertEquals( Integer.MAX_VALUE, problem.getColumnNumber() ); problem = new DefaultProblem( null, null, null, -1, Integer.MIN_VALUE, null ); assertEquals( Integer.MIN_VALUE, problem.getColumnNumber() ); }