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| <div class="toc-item" style="margin-left:0"><a href="../guide/async.html"><strong>10</strong><span>Asynchronous Programming</span></a> |
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| <h1>10 Asynchronous Programming - Reference Documentation</h1> |
| |
| <p><strong>Authors:</strong> Graeme Rocher, Peter Ledbrook, Marc Palmer, Jeff Brown, Luke Daley, Burt Beckwith, Lari Hotari</p> |
| |
| <p><strong>Version:</strong> 3.0.0.RC2</p> |
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| <div id="table-of-content"> |
| <h2>Table of Contents</h2> |
| |
| <div class="toc-item" style="margin-left:0px"><a href="#promises"><strong>10.1</strong><span>Promises</span></a> |
| </div> |
| |
| <div class="toc-item" style="margin-left:0px"><a href="#events"><strong>10.2</strong><span>Events</span></a> |
| </div> |
| |
| <div class="toc-item" style="margin-left:10px"><a href="#consuming"><strong>10.2.1</strong><span>Consuming Events</span></a> |
| </div> |
| |
| <div class="toc-item" style="margin-left:10px"><a href="#notifying"><strong>10.2.2</strong><span>Event Notification</span></a> |
| </div> |
| |
| <div class="toc-item" style="margin-left:0px"><a href="#asyncGorm"><strong>10.3</strong><span>Asynchronous GORM</span></a> |
| </div> |
| |
| <div class="toc-item" style="margin-left:0px"><a href="#asyncRequests"><strong>10.4</strong><span>Asynchronous Request Handling</span></a> |
| </div> |
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| <div class="toc-item" style="margin-left:0px"><a href="#asyncServletApi"><strong>10.5</strong><span>Servlet 3.0 Async</span></a> |
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| |
| <a name="8 Asynchronous Programming"><!-- Legacy link --></a> |
| <h1 id="async">10 Asynchronous Programming</h1> |
| With modern hardware featuring multiple cores, many programming languages have been adding asynchronous, parallel programming APIs, Groovy being no exception.<p class="paragraph"/>The excellent <a href="http://gpars.codehaus.org" target="blank">GPars</a> project features a whole range of different APIs for asynchronous programming techniques including actors, promises, STM and data flow concurrency.<p class="paragraph"/>Added Grails 2.3, the Async features of Grails aim to simplify concurrent programming within the framework and include the concept of Promises and a unified event model. |
| |
| |
| <h2 id="promises">10.1 Promises</h2> |
| A Promise is a concept being embraced by many concurrency frameworks. They are similar to <code>java.util.concurrent.Future</code> instances, but include a more user friendly exception handling model, useful features like chaining and the ability to attach listeners.<p class="paragraph"/><h3>Promise Basics</h3><p class="paragraph"/>In Grails the <code>grails.async.Promises</code> class provides the entry point to the Promise API:<p class="paragraph"/><div class="code"><pre><span class="java-keyword">import</span> <span class="java-keyword">static</span> grails.async.Promises.*</pre></div><p class="paragraph"/>To create promises you can use the <code>task</code> method, which returns an instance of the <code>grails.async.Promise</code> interface:<p class="paragraph"/><div class="code"><pre>def p1 = task { 2 * 2 } |
| def p2 = task { 4 * 4 } |
| def p3 = task { 8 * 8 } |
| assert [4,16,64] == waitAll(p1, p2, p3)</pre></div><p class="paragraph"/>The <code>waitAll</code> method waits synchronously, blocking the current thread, for all of the concurrent tasks to complete and returns the results.<p class="paragraph"/>If you prefer not to block the current thread you can use the <code>onComplete</code> method:<p class="paragraph"/><div class="code"><pre>onComplete([p1,p2,p3]) { List results -> |
| assert [4,16,64] == results |
| }</pre></div><p class="paragraph"/>The <code>waitAll</code> method will throw an exception if an error occurs executing one of the promises. The originating exception will be thrown. The <code>onComplete</code> method, however, will simply not execute the passed closure if an exception occurs. You can register an <code>onError</code> listener if you wish to handle exceptions without blocking:<p class="paragraph"/><div class="code"><pre>onError([p1,p2,p3]) { Throwable t -> |
| println <span class="java-quote">"An error occured ${t.message}"</span> |
| }</pre></div><p class="paragraph"/>If you have just a single long running promise then the <code>grails.async.Promise</code> interface provides a similar API on the promise itself. For example:<p class="paragraph"/><div class="code"><pre><span class="java-keyword">import</span> <span class="java-keyword">static</span> java.util.concurrent.TimeUnit.* |
| <span class="java-keyword">import</span> <span class="java-keyword">static</span> grails.async.Promises.*<p class="paragraph"/>Promise p = task { |
| // <span class="java-object">Long</span> running task |
| } |
| p.onError { Throwable err -> |
| println <span class="java-quote">"An error occured ${err.message}"</span> |
| } |
| p.onComplete { result -> |
| println <span class="java-quote">"Promise returned $result"</span> |
| } |
| // block until result is called |
| def result = p.get() |
| // block <span class="java-keyword">for</span> the specified time |
| def result = p.get(1,MINUTES)</pre></div><p class="paragraph"/><h3>Promise Chaining</h3><p class="paragraph"/>It is possible to chain several promises and wait for the chain to complete using the <code>then</code> method:<p class="paragraph"/><div class="code"><pre><span class="java-keyword">final</span> polish = { … } |
| <span class="java-keyword">final</span> transform = { … } |
| <span class="java-keyword">final</span> save = { … } |
| <span class="java-keyword">final</span> notify = { … }<p class="paragraph"/>Promise promise = task { |
| // <span class="java-object">long</span> running task |
| } |
| promise.then polish then transform then save then { |
| // notify end result |
| }</pre></div><p class="paragraph"/>If an exception occurs at any point in the chain it will be propagated back to the caller and the next step in the chain will not be called.<p class="paragraph"/><h3>Promise Lists and Maps</h3><p class="paragraph"/>Grails' async API also features the concept of a promise lists and maps. These are represented by the <code>grails.async.PromiseList</code> and <code>grails.async.PromiseMap</code> classes respectively.<p class="paragraph"/>The easiest way to create a promise list or map is via the <code>tasks</code> method of the <code>Promises</code> class:<p class="paragraph"/><div class="code"><pre><span class="java-keyword">import</span> <span class="java-keyword">static</span> grails.async.Promises.*<p class="paragraph"/>def promiseList = tasks([{ 2 * 2 }, { 4 * 4}, { 8 * 8 }])<p class="paragraph"/>assert [4,16,64] == promiseList.get()</pre></div><p class="paragraph"/>The <code>tasks</code> method, when passed a list of closures, returns a <code>PromiseList</code>. You can also construct a <code>PromiseList</code> manually:<p class="paragraph"/><div class="code"><pre><span class="java-keyword">import</span> grails.async.*<p class="paragraph"/>def list = <span class="java-keyword">new</span> PromiseList() |
| list << { 2 * 2 } |
| list << { 4 * 4 } |
| list << { 8 * 8 } |
| list.onComplete { List results -> |
| assert [4,16,64] == results |
| }</pre></div><p class="paragraph"/><blockquote class="note"> |
| The <code>PromiseList</code> class does not implement the java.util.List interface, but instead returns a java.util.List from the get() method |
| </blockquote><p class="paragraph"/>Working with <code>PromiseMap</code> instances is largely similar. Again you can either use the <code>tasks</code> method:<p class="paragraph"/> |
| <div class="code"><pre><span class="java-keyword">import</span> <span class="java-keyword">static</span> grails.async.Promises.*<p class="paragraph"/>def promiseList = tasks one:{ 2 * 2 }, |
| two:{ 4 * 4}, |
| three:{ 8 * 8 }<p class="paragraph"/>assert [one:4,two:16,three:64] == promiseList.get()</pre></div><p class="paragraph"/>Or construct a <code>PromiseMap</code> manually:<p class="paragraph"/><div class="code"><pre><span class="java-keyword">import</span> grails.async.*<p class="paragraph"/>def map = <span class="java-keyword">new</span> PromiseMap() |
| map['one'] = { 2 * 2 } |
| map['two'] = { 4 * 4 } |
| map['three'] = { 8 * 8 } |
| map.onComplete { Map results -> |
| assert [one:4,two:16,three:64] == results |
| }</pre></div><p class="paragraph"/><h3>Promise Factories</h3><p class="paragraph"/>The <code>Promises</code> class uses a <code>grails.async.PromiseFactory</code> instance to create <code>Promise</code> instances.<p class="paragraph"/>The default implementation uses the GPars concurrency library and is called <code>org.grails.async.factory.gpars.GparsPromiseFactory</code>, however it is possible to swap implementations by setting the <code>Promises.promiseFactory</code> variable.<p class="paragraph"/>One common use case for this is unit testing, typically you do not want promises to execute asynchronously during unit tests, as this makes tests harder to write. For this purpose Grails ships with a <code>org.grails.async.factory.SynchronousPromiseFactory</code> instance that makes it easier to test promises:<p class="paragraph"/><div class="code"><pre><span class="java-keyword">import</span> org.grails.async.factory.* |
| <span class="java-keyword">import</span> grails.async.*<p class="paragraph"/>Promises.promiseFactory = <span class="java-keyword">new</span> SynchronousPromiseFactory()</pre></div><p class="paragraph"/>Using the <code>PromiseFactory</code> mechanism is theoretically possible to plug in other concurrency libraries into the Grails framework.<p class="paragraph"/><h3>DelegateAsync Transformation</h3><p class="paragraph"/>It is quite common to require both synchronous and asynchronous versions of the same API. Developing both can result in a maintenance problem as typically the asynchronous API would simply delegate to the synchronous version.<p class="paragraph"/>The <code>DelegateAsync</code> transformation is designed to mitigate this problem by transforming any synchronous API into an asynchronous one.<p class="paragraph"/>For example, consider the following service:<p class="paragraph"/><div class="code"><pre>class BookService { |
| List<Book> findBooks(<span class="java-object">String</span> title) { |
| // implementation |
| } |
| }</pre></div><p class="paragraph"/>The <code>findBooks</code> method executes synchronously in the same thread as the caller. To make an asynchronous version of this API you can define another class as follows:<p class="paragraph"/><div class="code"><pre><span class="java-keyword">import</span> grails.async.*<p class="paragraph"/>class AsyncBookService { |
| @DelegateAsync BookService bookService |
| }</pre></div><p class="paragraph"/>The <code>DelegateAsync</code> transformation will automatically add a new method that looks like the following to the <code>AsyncBookService</code> class:<p class="paragraph"/><div class="code"><pre>Promise<List<Book>> findBooks(<span class="java-object">String</span> title) { |
| Promises.task { |
| bookService.findBooks(title) |
| } |
| }</pre></div><p class="paragraph"/>As you see the transform adds equivalent methods that return a Promise and execute asynchronously.<p class="paragraph"/>The <code>AsyncBookService</code> can then be injected into other controllers and services and used as follows:<p class="paragraph"/><div class="code"><pre>AsyncBookService asyncBookService |
| def findBooks(<span class="java-object">String</span> title) { |
| asyncBookService.findBooks(title) |
| .onComplete { List results -> |
| println <span class="java-quote">"Books = ${results}"</span> |
| } |
| }</pre></div> |
| |
| |
| <a name="4.3 Hooking into Events"><!-- Legacy link --></a> |
| <h2 id="events">10.2 Events</h2> |
| Grails 3.0 introduces a new Events API based on <a href="https://github.com/reactor/reactor" target="blank">Reactor</a>.<p class="paragraph"/>All services and controllers in Grails 3.0 implement the <a href="http://grails.org/doc/3.0.x/api/grails/events/Events.html" class="api">Events</a> trait.<p class="paragraph"/>The <code>Events</code> trait allows the ability to consume and publish events that are handled by Reactor.<p class="paragraph"/>The default Reactor configuration utilises a thread pool backed event bus. You can however configure Reactor within <code>application.yml</code>, for example:<p class="paragraph"/><div class="code"><pre>reactor |
| dispatchers: |
| <span class="java-keyword">default</span>: myExecutor |
| myExecutor: |
| type: threadPoolExecutor |
| size: 5 |
| backlog: 2048</pre></div> |
| |
| |
| |
| <h2 id="consuming">10.2.1 Consuming Events</h2> |
| There are several ways to consume an event. As mentioned previously services and controllers implement the <a href="http://grails.org/doc/3.0.x/api/grails/events/Events.html" class="api">Events</a> trait.<p class="paragraph"/>The <code>Events</code> trait provides several methods to register event consumers. For example:<p class="paragraph"/><div class="code"><pre>on(<span class="java-quote">"myEvent"</span>) { |
| println <span class="java-quote">"Event fired!"</span> |
| }</pre></div><p class="paragraph"/>Note that if you wish a class (other than a controller or service) to be an event consumer you simply have to implement the <code>Events</code> trait and ensure the class is registered as a Spring bean. |
| |
| |
| |
| <h2 id="notifying">10.2.2 Event Notification</h2> |
| The <code>Events</code> trait also provides methods for notifying of events. For example:<p class="paragraph"/><div class="code"><pre>notify <span class="java-quote">"myEvent"</span>, <span class="java-quote">"myData"</span> |
| sendAndReceive <span class="java-quote">"myEvent"</span>, <span class="java-quote">"myData"</span>, { |
| println <span class="java-quote">"Got response!"</span> |
| }</pre></div> |
| |
| |
| |
| <h2 id="asyncGorm">10.3 Asynchronous GORM</h2> |
| Since Grails 2.3, GORM features an asynchronous programming model that works across all supported datastores (Hibernate, MongoDB etc.).<p class="paragraph"/><h3>Async Namespace</h3><p class="paragraph"/>The Asynchronous GORM API is available on every domain class via the <code>async</code> namespace.<p class="paragraph"/>For example, the following code listing reads 3 objects from the database asynchronously:<p class="paragraph"/><div class="code"><pre><span class="java-keyword">import</span> <span class="java-keyword">static</span> grails.async.Promises.*<p class="paragraph"/>def p1 = Person.async.get(1L) |
| def p2 = Person.async.get(2L) |
| def p3 = Person.async.get(3L) |
| def results = waitAll(p1, p2, p3)</pre></div><p class="paragraph"/>Using the <code>async</code> namespace, all the regular GORM methods are available (even dynamic finders), but instead of executing synchronously, the query is run in the background and a <code>Promise</code> instance is returned.<p class="paragraph"/>The following code listing shows a few common examples of GORM queries executed asynchronously:<p class="paragraph"/><div class="code"><pre><span class="java-keyword">import</span> <span class="java-keyword">static</span> grails.async.Promises.*<p class="paragraph"/>Person.async.list().onComplete { List results -> |
| println <span class="java-quote">"Got people = ${results}"</span> |
| } |
| def p = Person.async.getAll(1L, 2L, 3L) |
| List results = p.get()<p class="paragraph"/>def p1 = Person.async.findByFirstName(<span class="java-quote">"Homer"</span>) |
| def p2 = Person.async.findByFirstName(<span class="java-quote">"Bart"</span>) |
| def p3 = Person.async.findByFirstName(<span class="java-quote">"Barney"</span>) |
| results = waitAll(p1, p2, p3)</pre></div><p class="paragraph"/><h3>Async and the Session</h3><p class="paragraph"/>When using GORM async each promise is executed in a different thread. Since the Hibernate session is not concurrency safe, a new session is bound per thread.<p class="paragraph"/>This is an important consideration when using GORM async (particularly with Hibernate as the persistence engine). The objects returned from asynchronous queries will be detached entities.<p class="paragraph"/>This means you cannot save objects returned from asynchronous queries without first merging them back into session. For example the following will not work:<p class="paragraph"/><div class="code"><pre>def promise = Person.async.findByFirstName(<span class="java-quote">"Homer"</span>) |
| def person = promise.get() |
| person.firstName = <span class="java-quote">"Bart"</span> |
| person.save()</pre></div><p class="paragraph"/>Instead you need to merge the object with the session bound to the calling thread. The above code needs to be written as:<p class="paragraph"/><div class="code"><pre>def promise = Person.async.findByFirstName(<span class="java-quote">"Homer"</span>) |
| def person = promise.get() |
| person.merge() |
| person.firstName = <span class="java-quote">"Bart"</span></pre></div><p class="paragraph"/>Note that <code>merge()</code> is called first because it may refresh the object from the cache or database, which would result in the change being lost. In general it is not recommended to read and write objects in different threads and you should avoid this technique unless absolutely necessary.<p class="paragraph"/>Finally, another issue with detached objects is that association lazy loading <strong class="bold">will not</strong> work and you will encounter <code>LazyInitializationException</code> errors if you do so. If you plan to access the associated objects of those returned from asynchronous queries you should use eager queries (which is recommended anyway to avoid N+1 problems).<p class="paragraph"/><h3>Multiple Asynchronous GORM calls</h3><p class="paragraph"/>As discussed in the previous section you should avoid reading and writing objects in different threads as merging tends to be inefficient.<p class="paragraph"/>However, if you wish to do more complex GORM work asynchronously then the GORM async namespace provides a <code>task</code> method that makes this possible. For example:<p class="paragraph"/><div class="code"><pre>def promise = Person.async.task { |
| withTransaction { |
| def person = findByFirstName(<span class="java-quote">"Homer"</span>) |
| person.firstName = <span class="java-quote">"Bart"</span> |
| person.save(flush:<span class="java-keyword">true</span>) |
| } |
| }<p class="paragraph"/>Person updatedPerson = promise.get()</pre></div><p class="paragraph"/>Note that the GORM <code>task</code> method differs from the static <code>Promises.task</code> method in that it deals with binding a new session to the asynchronous thread for you. If you do not use the GORM version and do asynchronous work with GORM then you need to do this manually. Example:<p class="paragraph"/><div class="code"><pre><span class="java-keyword">import</span> <span class="java-keyword">static</span> grails.async.Promises.*<p class="paragraph"/>def promise = task { |
| Person.withNewSession { |
| // your logic here |
| } |
| }</pre></div><p class="paragraph"/><h3>Async DetachedCriteria</h3><p class="paragraph"/>The <code>DetachedCriteria</code> class also supports the <code>async</code> namespace. For example you can do the following:<p class="paragraph"/><div class="code"><pre>DetachedCriteria query = Person.where { |
| lastName == <span class="java-quote">"Simpson"</span> |
| }<p class="paragraph"/>def promise = query.async.list()</pre></div><p class="paragraph"/><p class="paragraph"/> |
| |
| |
| <h2 id="asyncRequests">10.4 Asynchronous Request Handling</h2> |
| If you are deploying to a Servlet 3.0 container such as Tomcat 7 and above then it is possible to deal with responses asynchronously.<p class="paragraph"/>In general for controller actions that execute quickly there is little benefit in handling requests asynchronously. However, for long running controller actions it is extremely beneficial.<p class="paragraph"/>The reason being that with an asynchronous / non-blocking response, the one thread == one request == one response relationship is broken. The container can keep a client response open and active, and at the same time return the thread back to the container to deal with another request, improving scalability.<p class="paragraph"/>For example, if you have 70 available container threads and an action takes a minute to complete, if the actions are not executed in a non-blocking fashion the likelihood of all 70 threads being occupied and the container not being able to respond is quite high and you should consider asynchronous request processing.<p class="paragraph"/>Since Grails 2.3, Grails features a simplified API for creating asynchronous responses built on the <code>Promise</code> mechanism discussed previously.<p class="paragraph"/>The implementation is based on Servlet 3.0 async so to enable the async features you need to set your servlet target version to 3.0 in BuildConfig.groovy:<p class="paragraph"/><div class="code"><pre>grails.servlet.version = <span class="java-quote">"3.0"</span></pre></div><p class="paragraph"/><h4>Async Models</h4><p class="paragraph"/>A typical activity in a Grails controller is to produce a model (a map of key/value pairs) that can be rendered by a view.<p class="paragraph"/>If the model takes a while to produce then the server could arrive at a blocking state, impacting scalability. You tell Grails to build the model asynchronously by returning a <code>grails.async.PromiseMap</code> via the <code>Promises.tasks</code> method:<p class="paragraph"/><div class="code"><pre><span class="java-keyword">import</span> <span class="java-keyword">static</span> grails.async.Promises.* |
| … |
| def index() { |
| tasks books: Book.async.list(), |
| totalBooks: Book.async.count(), |
| otherValue: { |
| // <span class="java-keyword">do</span> hard work |
| } |
| }</pre></div><p class="paragraph"/>Grails will handle the response asynchronously, waiting for the promises to complete before rendering the view. The equivalent synchronous action of the above is:<p class="paragraph"/><div class="code"><pre>def index() { |
| def otherValue = … |
| [ books: Book.list() , |
| totalBooks: Book.count(), |
| otherValue: otherValue ] |
| }</pre></div><p class="paragraph"/>You can even render different view by passing the <code>PromiseMap</code> to the <code>model</code> attribute of the <code>render</code> method:<p class="paragraph"/><div class="code"><pre><span class="java-keyword">import</span> <span class="java-keyword">static</span> grails.async.Promises.* |
| … |
| def index() { |
| render view:<span class="java-quote">"myView"</span>, model: tasks( one:{ 2 * 2 }, |
| two:{ 3 * 3 } ) |
| }</pre></div><p class="paragraph"/><h4>Async Response Rendering</h4><p class="paragraph"/>You can also write to the response asynchronously using promises in Grails 2.3 and above:<p class="paragraph"/><div class="code"><pre><span class="java-keyword">import</span> <span class="java-keyword">static</span> grails.async.Promises.* |
| class StockController {<p class="paragraph"/> def stock(<span class="java-object">String</span> ticker) { |
| task { |
| ticker = ticker ?: 'GOOG' |
| def url = <span class="java-keyword">new</span> URL(<span class="java-quote">"http://download.finance.yahoo.com/d/quotes.csv?s=${ticker}&f=nsl1op&e=.csv"</span>) |
| <span class="java-object">Double</span> price = url.text.split(',')[-1] as <span class="java-object">Double</span> |
| render <span class="java-quote">"ticker: $ticker, price: $price"</span> |
| } |
| } |
| }</pre></div><p class="paragraph"/>The above example using Yahoo Finance to query stock prices, executing asynchronously and only rendering the response once the result has been obtained. This is done by returning a <code>Promise</code> instance from the controller action.<p class="paragraph"/>If the Yahoo URL is unresponsive the original request thread will not be blocked and the container will not become unresponsive. |
| |
| |
| |
| <h2 id="asyncServletApi">10.5 Servlet 3.0 Async</h2> |
| In addition to the higher level async features discussed earlier in the section, you can access the raw Servlet 3.0 asynchronous API from a Grails application.<p class="paragraph"/><h4>Servlet 3.0 Asynchronous Rendering</h4><p class="paragraph"/>You can render content (templates, binary data etc.) in an asynchronous manner by calling the <code>startAsync</code> method which returns an instance of the Servlet 3.0 <code>AsyncContext</code>. Once you have a reference to the <code>AsyncContext</code> you can use Grails' regular render method to render content:<p class="paragraph"/><div class="code"><pre>def index() { |
| def ctx = startAsync() |
| ctx.start { |
| <span class="java-keyword">new</span> Book(title:<span class="java-quote">"The Stand"</span>).save() |
| render template:<span class="java-quote">"books"</span>, model:[books:Book.list()] |
| ctx.complete() |
| } |
| }</pre></div><p class="paragraph"/>Note that you must call the <code>complete()</code> method to terminate the connection.<p class="paragraph"/><h4>Resuming an Async Request</h4><p class="paragraph"/>You resume processing of an async request (for example to delegate to view rendering) by using the <code>dispatch</code> method of the <code>AsyncContext</code> class:<p class="paragraph"/><div class="code"><pre>def index() { |
| def ctx = startAsync() |
| ctx.start { |
| // <span class="java-keyword">do</span> working |
| … |
| // render view |
| ctx.dispatch() |
| } |
| }</pre></div> |
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| <div class="menu-item"><a href="../ref/Domain%20Classes/hasMany.html">hasMany</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Domain%20Classes/hasOne.html">hasOne</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Domain%20Classes/ident.html">ident</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Domain%20Classes/instanceOf.html">instanceOf</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Domain%20Classes/isAttached.html">isAttached</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Domain%20Classes/isDirty.html">isDirty</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Domain%20Classes/last.html">last</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Domain%20Classes/list.html">list</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Domain%20Classes/listOrderBy.html">listOrderBy</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Domain%20Classes/load.html">load</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Domain%20Classes/lock.html">lock</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Domain%20Classes/mapWith.html">mapWith</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Domain%20Classes/mappedBy.html">mappedBy</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Domain%20Classes/mapping.html">mapping</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Domain%20Classes/merge.html">merge</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Domain%20Classes/namedQueries.html">namedQueries</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Domain%20Classes/properties.html">properties</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Domain%20Classes/read.html">read</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Domain%20Classes/refresh.html">refresh</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Domain%20Classes/removeFrom.html">removeFrom</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Domain%20Classes/save.html">save</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Domain%20Classes/transients.html">transients</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Domain%20Classes/validate.html">validate</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Domain%20Classes/where.html">where</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Domain%20Classes/whereAny.html">whereAny</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Domain%20Classes/withCriteria.html">withCriteria</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Domain%20Classes/withNewSession.html">withNewSession</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Domain%20Classes/withSession.html">withSession</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Domain%20Classes/withTransaction.html">withTransaction</a> |
| </div> |
| |
| </div> |
| </div> |
| |
| <div class="menu-block"><h1 class="menu-title" onclick="toggleRef(this.parentNode.childNodes[1])">Plug-ins</h1><div class="menu-sub"> |
| |
| <div class="menu-item"><a href="../ref/Plug-ins/Usage.html">Usage</a></div> |
| |
| |
| <div class="menu-item"><a href="../ref/Plug-ins/URL%20mappings.html">URL mappings</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Plug-ins/codecs.html">codecs</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Plug-ins/controllers.html">controllers</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Plug-ins/core.html">core</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Plug-ins/dataSource.html">dataSource</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Plug-ins/domainClasses.html">domainClasses</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Plug-ins/hibernate.html">hibernate</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Plug-ins/i18n.html">i18n</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Plug-ins/logging.html">logging</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Plug-ins/scaffolding.html">scaffolding</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Plug-ins/services.html">services</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Plug-ins/servlets.html">servlets</a> |
| </div> |
| |
| </div> |
| </div> |
| |
| <div class="menu-block"><h1 class="menu-title" onclick="toggleRef(this.parentNode.childNodes[1])">Services</h1><div class="menu-sub"> |
| |
| <div class="menu-item"><a href="../ref/Services/Usage.html">Usage</a></div> |
| |
| |
| <div class="menu-item"><a href="../ref/Services/scope.html">scope</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Services/transactional.html">transactional</a> |
| </div> |
| |
| </div> |
| </div> |
| |
| <div class="menu-block"><h1 class="menu-title" onclick="toggleRef(this.parentNode.childNodes[1])">Servlet API</h1><div class="menu-sub"> |
| |
| |
| <div class="menu-item"><a href="../ref/Servlet%20API/request.html">request</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Servlet%20API/response.html">response</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Servlet%20API/servletContext.html">servletContext</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Servlet%20API/session.html">session</a> |
| </div> |
| |
| </div> |
| </div> |
| |
| <div class="menu-block"><h1 class="menu-title" onclick="toggleRef(this.parentNode.childNodes[1])">Tag Libraries</h1><div class="menu-sub"> |
| |
| <div class="menu-item"><a href="../ref/Tag%20Libraries/Usage.html">Usage</a></div> |
| |
| |
| <div class="menu-item"><a href="../ref/Tag%20Libraries/actionName.html">actionName</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tag%20Libraries/controllerName.html">controllerName</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tag%20Libraries/flash.html">flash</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tag%20Libraries/pageScope.html">pageScope</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tag%20Libraries/params.html">params</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tag%20Libraries/request.html">request</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tag%20Libraries/response.html">response</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tag%20Libraries/servletContext.html">servletContext</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tag%20Libraries/session.html">session</a> |
| </div> |
| |
| </div> |
| </div> |
| |
| <div class="menu-block"><h1 class="menu-title" onclick="toggleRef(this.parentNode.childNodes[1])">Tags</h1><div class="menu-sub"> |
| |
| |
| <div class="menu-item"><a href="../ref/Tags/actionSubmit.html">actionSubmit</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/actionSubmitImage.html">actionSubmitImage</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/applyLayout.html">applyLayout</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/checkBox.html">checkBox</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/collect.html">collect</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/cookie.html">cookie</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/country.html">country</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/countrySelect.html">countrySelect</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/createLink.html">createLink</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/createLinkTo.html">createLinkTo</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/currencySelect.html">currencySelect</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/datePicker.html">datePicker</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/each.html">each</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/eachError.html">eachError</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/else.html">else</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/elseif.html">elseif</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/external.html">external</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/field.html">field</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/fieldValue.html">fieldValue</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/findAll.html">findAll</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/form.html">form</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/formatBoolean.html">formatBoolean</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/formatDate.html">formatDate</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/formatNumber.html">formatNumber</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/grep.html">grep</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/hasErrors.html">hasErrors</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/header.html">header</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/hiddenField.html">hiddenField</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/if.html">if</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/img.html">img</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/include.html">include</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/isAvailable.html">isAvailable</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/isNotAvailable.html">isNotAvailable</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/javascript.html">javascript</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/join.html">join</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/layoutBody.html">layoutBody</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/layoutHead.html">layoutHead</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/layoutTitle.html">layoutTitle</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/link.html">link</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/localeSelect.html">localeSelect</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/message.html">message</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/meta.html">meta</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/pageProperty.html">pageProperty</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/paginate.html">paginate</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/passwordField.html">passwordField</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/radio.html">radio</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/radioGroup.html">radioGroup</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/render.html">render</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/renderErrors.html">renderErrors</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/resource.html">resource</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/select.html">select</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/set.html">set</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/sortableColumn.html">sortableColumn</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/submitButton.html">submitButton</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/textArea.html">textArea</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/textField.html">textField</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/timeZoneSelect.html">timeZoneSelect</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/unless.html">unless</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/uploadForm.html">uploadForm</a> |
| </div> |
| |
| <div class="menu-item"><a href="../ref/Tags/while.html">while</a> |
| </div> |
| |
| </div> |
| </div> |
| |
| </div> |
| </div> |
| </td> |
| </tr> |
| </table> |
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