getConstraint() public method

public getConstraint ( long n ) : Constraint
n long
return Constraint
 public void test_Constraint_parent_create()
 {
     Model m = new Model(2,4);
       Constraint ct = m.createConstraint();
       ListOf lo = m.getListOfConstraints();
       assertTrue( lo == m.getConstraint(0).getParentSBMLObject() );
       assertTrue( lo == ct.getParentSBMLObject() );
       assertTrue( m == lo.getParentSBMLObject() );
 }
 public void test_Constraint_ancestor_create()
 {
     Model m = new Model(2,4);
       Constraint ct = m.createConstraint();
       ListOf lo = m.getListOfConstraints();
       assertTrue( ct.getAncestorOfType(libsbml.SBML_MODEL) == m );
       assertTrue( ct.getAncestorOfType(libsbml.SBML_LIST_OF) == lo );
       assertTrue( ct.getAncestorOfType(libsbml.SBML_DOCUMENT) == null );
       assertTrue( ct.getAncestorOfType(libsbml.SBML_EVENT) == null );
       Constraint obj = m.getConstraint(0);
       assertTrue( obj.getAncestorOfType(libsbml.SBML_MODEL) == m );
       assertTrue( obj.getAncestorOfType(libsbml.SBML_LIST_OF) == lo );
       assertTrue( obj.getAncestorOfType(libsbml.SBML_DOCUMENT) == null );
       assertTrue( obj.getAncestorOfType(libsbml.SBML_EVENT) == null );
 }
 public void test_Constraint_parent_add()
 {
     Constraint ct = new Constraint(2,4);
       Model m = new Model(2,4);
       ct.setMath(libsbml.parseFormula("a-k"));
       m.addConstraint(ct);
       ct = null;
       ListOf lo = m.getListOfConstraints();
       assertTrue( lo == m.getConstraint(0).getParentSBMLObject() );
       assertTrue( m == lo.getParentSBMLObject() );
 }
 public void test_Constraint_ancestor_add()
 {
     Constraint ct = new Constraint(2,4);
       Model m = new Model(2,4);
       ct.setMath(libsbml.parseFormula("k+k"));
       m.addConstraint(ct);
       ct = null;
       ListOf lo = m.getListOfConstraints();
       Constraint obj = m.getConstraint(0);
       assertTrue( obj.getAncestorOfType(libsbml.SBML_MODEL) == m );
       assertTrue( obj.getAncestorOfType(libsbml.SBML_LIST_OF) == lo );
       assertTrue( obj.getAncestorOfType(libsbml.SBML_DOCUMENT) == null );
       assertTrue( obj.getAncestorOfType(libsbml.SBML_EVENT) == null );
 }