contains method still not validating properly? any problem my bean class

contains method still not validating properly

in the chargelist i have charges 162,620;

chargelist contains other than 620 i.e 162 chargeid exists in the list why it is not entering into if loop;


   if(chargesList!=null && chargesList.size()>0)
            {
    if (!chargesList.contains( new HouseDocumentCharges("620")) )
    {
                        userInputModel = new UserInputModel(vndrList,"vendorIdLabel", ValidationConstants.MULTI_VENDOR_VALIDATION_NAME,4);//changed validation code from 3 to 4
                        validationModel.addUserInput("Vendor(s)",userInputModel);
    }


 any problem my bean class

public class HouseDocumentCharges implements Serializable,Cloneable
{

      public String            costIncurredAt;
      
      public String            chargeId;
      public String            chargeDescription;
      

       public HouseDocumentCharges(String chargeId) {
       this.chargeId = chargeId;
   }

  public boolean equals(Object obj) {
       return chargeId.equals( ((HouseDocumentCharges)obj).chargeId );
   }
   public int hashCode() {
       return chargeId.hashCode();
   }

}
    }