@Override
  public void setString( String string ) {
    this.string = string;
  }
@Test
  public void testSetString() {
    ValueString vs = new ValueString();

    vs.setString( null );
    assertNull( vs.getString() );
    vs.setString( "" );
    assertEquals( "", vs.getString() );
    vs.setString( "Boden" );
    assertEquals( "Boden", vs.getString() );
  }