@Data
@Entity
public class Employee {
private @Id @GeneratedValue Long id;
private String firstName;
private String lastName;
private String description;

private @Version @JsonIgnore Long version;

private Employee() {}

public Employee(String firstName, String lastName, String description) {
	this.firstName = firstName;
	this.lastName = lastName;
	this.description = description;
}

}

loadFromServer: function (pageSize) {
    follow(client, root, [
        {rel: 'employees', params: {size: pageSize}}]
    ).then(employeeCollection => {
        return client({
            method: 'GET',
            path: employeeCollection.entity._links.profile.href,
            headers: {'Accept': 'application/schema+json'}
        }).then(schema => {
            this.schema = schema.entity;
            this.links = employeeCollection.entity._links;
            return employeeCollection;
        });
    }).then(employeeCollection => {
        return employeeCollection.entity._embedded.employees.map(employee =>
                client({
                    method: 'GET',
                    path: employee._links.self.href
                })
        );
    }).then(employeePromises => {
        return when.all(employeePromises);
    }).done(employees => {
        this.setState({
            employees: employees,
            attributes: Object.keys(this.schema.properties),
            pageSize: pageSize,
            links: this.links
        });
    });
},

var UpdateDialog = React.createClass({
handleSubmit: function (e) {
    e.preventDefault();
    var updatedEmployee = {};
    this.props.attributes.forEach(attribute => {
        updatedEmployee[attribute] = React.findDOMNode(this.refs[attribute]).value.trim();
    });
    this.props.onUpdate(this.props.employee, updatedEmployee);
    window.location = "#";
},

render: function () {
    var inputs = this.props.attributes.map(attribute =>
            <p key={this.props.employee.entity[attribute]}>
                <input type="text" placeholder={attribute}
                       defaultValue={this.props.employee.entity[attribute]}
                       ref={attribute} className="field" />
            </p>
    );

    var dialogId = "updateEmployee-" + this.props.employee.entity._links.self.href;

    return (
        <div key={this.props.employee.entity._links.self.href}>
            <a href={"#" + dialogId}>Update</a>
            <div id={dialogId} className="modalDialog">
                <div>
                    <a href="#" title="Close" className="close">X</a>

                    <h2>Update an employee</h2>

                    <form>
                        {inputs}
                        <button onClick={this.handleSubmit}>Update</button>
                    </form>
                </div>
            </div>
        </div>
    )
}

});

onUpdate: function (employee, updatedEmployee) {
    client({
        method: 'PUT',
        path: employee.entity._links.self.href,
        entity: updatedEmployee,
        headers: {
            'Content-Type': 'application/json',
            'If-Match': employee.headers.Etag
        }
    }).done(response => {
        this.loadFromServer(this.state.pageSize);
    }, response => {
        if (response.status.code === 412) {
            alert('DENIED: Unable to update ' +
                employee.entity._links.self.href + '. Your copy is stale.');
        }
    });
},

var Employee = React.createClass({
    handleDelete: function () {
        this.props.onDelete(this.props.employee);
    },
    render: function () {
        return (
            <tr>
                <td>{this.props.employee.entity.firstName}</td>
                <td>{this.props.employee.entity.lastName}</td>
                <td>{this.props.employee.entity.description}</td>
                <td>
                    <UpdateDialog employee={this.props.employee}
                                  attributes={this.props.attributes}
                                  onUpdate={this.props.onUpdate}/>
                </td>
                <td>
                    <button onClick={this.handleDelete}>Delete</button>
                </td>
            </tr>
        )
    }
})

Seeing things in action

1. Start up the app (./mvnw spring-boot:run).
2. Open up a tab and navigate to http://localhost:8080.
   
3. Pull up the edit dialog for Frodo.
4. Open another tab in your browser and pull up the same record.
5. Make a change to the record in the first tab.
6. Try to make a change in the second tab.
   

With these mods, you have increased data integrity by avoiding collisions.