Package org.faktorips.codegen.dthelpers

Class ListOfValueDatatypeHelper

java.lang.Object
org.faktorips.codegen.dthelpers.AbstractDatatypeHelper
org.faktorips.codegen.dthelpers.ListOfValueDatatypeHelper
All Implemented Interfaces:
BaseDatatypeHelper<JavaCodeFragment>, DatatypeHelper
public class ListOfValueDatatypeHelper extends AbstractDatatypeHelper
A helper class for lists of values. There is no data type for lists though. The data type specified in the constructor is the data type of the elements in the list. valueOfExpression(String) expects a list as expression and returns code that creates a copy of that list. newInstance(String) returns code that creates an empty list. The given value will be ignored.
Author:
Stefan Widmaier

  • Constructor Details

    • ListOfValueDatatypeHelper

      public ListOfValueDatatypeHelper(DatatypeHelper elementDatatypeHelper)

  • Method Details

    • getDatatype

      public ListOfTypeDatatype getDatatype()
      Description copied from interface: DatatypeHelper
      Returns the datatype this is a helper for.
      Specified by:
      getDatatype in interface BaseDatatypeHelper<JavaCodeFragment>
      Specified by:
      getDatatype in interface DatatypeHelper
      Overrides:
      getDatatype in class AbstractDatatypeHelper

    • getBasicDatatype

      public Datatype getBasicDatatype()
      Returns the ValueDatatype of the elements in the list.

    • getBasicJavaClassName

      public String getBasicJavaClassName()

    • getJavaClassName

      public String getJavaClassName()
      Description copied from interface: DatatypeHelper
      Returns the qualified Java class name the datatype represents.

    • valueOfExpression

      protected JavaCodeFragment valueOfExpression(String expression)
      Expects a list as expression and returns code that creates a copy of that list. This method is supposed to be overridden by subclasses.

      It is used within the newInstanceFromExpression(String) method. It returns a JavaCodeFragment with sourcecode that creates an instance of the datatype's Java class with the given expression.

      If the expression is null the fragment's sourcecode is either the String "null" or the sourcecode to get an instance of the appropriate null object. Preconditions: Expression may not be null or empty. When evaluated the expression must return a String.

      Specified by:
      valueOfExpression in class AbstractDatatypeHelper

    • newInstance

      public JavaCodeFragment newInstance(String expression)
      Returns code that creates a list where the given expression is used as a constructor argument. Returns a JavaCodeFragment with sourcecode that creates an instance of the datatype's Java class with the given value. If the value is null the fragment's sourcecode is either the String "null" or the sourcecode to get an instance of the apropriate null object.

    • referenceOrSafeCopyIfNeccessary

      public JavaCodeFragment referenceOrSafeCopyIfNeccessary(String expression)
      Description copied from interface: DatatypeHelper
      If this is a helper for a mutable data type (like GregorianCalendar for example) this method return the code fragment that creates a copy of the given expression. For immutable data types this method returns the expression unmodified.
      Specified by:
      referenceOrSafeCopyIfNeccessary in interface DatatypeHelper
      Overrides:
      referenceOrSafeCopyIfNeccessary in class AbstractDatatypeHelper
      Parameters:
      expression - An expression (as Java sourcecode)
      Returns:
      s. above

    • getDeclarationJavaTypeFragment

      public JavaCodeFragment getDeclarationJavaTypeFragment()
      Returns code for a list-variable or -argument declarations. e.g. List<ElementJavaClassName>.