Database.com Metadata API Developer's Guide - Salesforce.com

CRUD-Based CallsdeleteMetadata()co.setDescription("Updated description");co.setLabel(name + " Object Update");co.setPluralLabel(co.getLabel() + "s");co.setSharingModel(SharingModel.ReadWrite);// Name field with a type and label is requiredCustomField cf = new CustomField();cf.setType(FieldType.Text);cf.setLabel(co.getFullName() + " Name");co.setNameField(cf);SaveResult[] results = metadataConnection.updateMetadata(new Metadata[] { co });}for (SaveResult r : results) {if (r.isSuccess()) {System.out.println("Updated component: " + r.getFullName());} else {System.out.println("Errors were encountered while updating "+ r.getFullName());for (Error e : r.getErrors()) {System.out.println("Error message: " + e.getMessage());System.out.println("Status code: " + e.getStatusCode());}}}} catch (ConnectionException ce) {ce.printStackTrace();}ArgumentsNamemetadataTypeMetadata[]DescriptionArray of one or more metadata components you wish to update.Limit: 10.You must submit arrays of only one type of component. For example,you could submit an array of 10 custom objects or 10 profiles, butnot a mix of both types.ResponseSaveResult[]deleteMetadata()Deletes one or more metadata components from your organization synchronously.SyntaxDeleteResult[] = metadataConnection.delete(string metadataType, string[] fullNames);UsageUse the deleteMetadata() call to delete one or more metadata components from your organization. This call executessynchronously, meaning the call returns only when the operation completes.You can use this call to delete any of the objects that extend Metadata. For more details, see Metadata Components and Types.51