Changing value of read-only attribute using plain java api

In 5.0 at least,you can not modify the work item attribute if it is set to read only. You can modify it if it is only read only in the editor presentations.

I doubt you can do it if prevent editing is set. Try it yourself. Here is some sample code:

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package com.ibm.js.team.workitem.automation.examples;

import java.net.URI;

import org.eclipse.core.runtime.IProgressMonitor;

import com.ibm.team.foundation.common.text.XMLString;
import com.ibm.team.process.client.IProcessClientService;
import com.ibm.team.process.common.IProjectArea;
import com.ibm.team.repository.client.ITeamRepository;
import com.ibm.team.repository.client.ITeamRepository.ILoginHandler;
import com.ibm.team.repository.client.ITeamRepository.ILoginHandler.ILoginInfo;
import com.ibm.team.repository.client.TeamPlatform;
import com.ibm.team.repository.common.TeamRepositoryException;
import com.ibm.team.workitem.client.IWorkItemClient;
import com.ibm.team.workitem.client.WorkItemOperation;
import com.ibm.team.workitem.client.WorkItemWorkingCopy;
import com.ibm.team.workitem.common.model.IAttribute;
import com.ibm.team.workitem.common.model.IWorkItem;
import com.ibm.team.workitem.common.model.IWorkItemReferences;

/**
 * Example code, see
 * https://jazz.net/wiki/bin/view/Main/ProgrammaticWorkItemCreation.
 */
public class ModifyWorkItemAttributeOperation {

	private static class LoginHandler implements ILoginHandler, ILoginInfo {

		private String fUserId;
		private String fPassword;

		private LoginHandler(String userId, String password) {
			fUserId = userId;
			fPassword = password;
		}

		public String getUserId() {
			return fUserId;
		}

		public String getPassword() {
			return fPassword;
		}

		public ILoginInfo challenge(ITeamRepository repository) {
			return this;
		}
	}

	private static class WorkItemSummaryModification extends WorkItemOperation {

		private String fAttributeId;
		private String fAttributeValueString;

		public WorkItemSummaryModification(String attributeId,
				String attributeValueString) {
			super("Modifying Work Item", IWorkItem.FULL_PROFILE);
			fAttributeId = attributeId;
			fAttributeValueString = attributeValueString;
		}

		@Override
		protected void execute(WorkItemWorkingCopy workingCopy,
				IProgressMonitor monitor) throws TeamRepositoryException {
			IWorkItem workItem = workingCopy.getWorkItem();
			ITeamRepository teamRepository = (ITeamRepository) workItem
					.getOrigin();
			IWorkItemClient workItemClient = (IWorkItemClient) teamRepository
					.getClientLibrary(IWorkItemClient.class);
			// workItem.setHTMLSummary(XMLString.createFromPlainText(fSummary));
			if (null != fAttributeId) {
				IAttribute customString = workItemClient.findAttribute(
						workItem.getProjectArea(), fAttributeId, monitor);
				if (workItem.hasCustomAttribute(customString))
					workItem.setValue(customString, fAttributeValueString);
			}
		}
	}

	public static void main(String[] args) {

		boolean result;
		TeamPlatform.startup();
		try {
			result = run(args);
		} catch (TeamRepositoryException x) {
			x.printStackTrace();
			result = false;
		} finally {
			TeamPlatform.shutdown();
		}

		if (!result)
			System.exit(1);
	}

	private static boolean run(String[] args) throws TeamRepositoryException {

		if (args.length != 7) {
			System.out
					.println("Usage: ModifyWorkItem       ");
			return false;
		}

		String repositoryURI = args[0];
		String userId = args[1];
		String password = args[2];
		String projectAreaName = args[3];
		String idString = args[4];
		String attributeId = args[5];
		String attributeValue = args[6];

		ITeamRepository teamRepository = TeamPlatform
				.getTeamRepositoryService().getTeamRepository(repositoryURI);
		teamRepository.registerLoginHandler(new LoginHandler(userId, password));
		teamRepository.login(null);

		IProcessClientService processClient = (IProcessClientService) teamRepository
				.getClientLibrary(IProcessClientService.class);
		IWorkItemClient workItemClient = (IWorkItemClient) teamRepository
				.getClientLibrary(IWorkItemClient.class);

		URI uri = URI.create(projectAreaName.replaceAll(" ", "%20"));
		IProjectArea projectArea = (IProjectArea) processClient
				.findProcessArea(uri, null, null);
		if (projectArea == null) {
			System.out.println("Project area not found.");
			return false;
		}

		int id = new Integer(idString).intValue();
		IWorkItem workItem = workItemClient.findWorkItemById(id,
				IWorkItem.FULL_PROFILE, null);

		WorkItemSummaryModification operation = new WorkItemSummaryModification(
				attributeId, attributeValue);
		operation.run(workItem, null);
		System.out.println("Modified work item " + workItem.getId() + ".");
		teamRepository.logout();

		return true;
	}
}