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diff --git a/docs/html/guide/topics/testing/contentprovider_testing.jd b/docs/html/guide/topics/testing/contentprovider_testing.jd new file mode 100644 index 0000000..893b5c9 --- /dev/null +++ b/docs/html/guide/topics/testing/contentprovider_testing.jd @@ -0,0 +1,224 @@ +page.title=Content Provider Testing +@jd:body + +<div id="qv-wrapper"> + <div id="qv"> + <h2>In this document</h2> + <ol> + <li> + <a href="#DesignAndTest">Content Provider Design and Testing</a> + </li> + <li> + <a href="#ContentProviderTestAPI">The Content Provider Testing API</a> + <ol> + <li> + <a href="#ProviderTestCase2">ProviderTestCase2 </a> + </li> + <li> + <a href="#MockObjects">Mock object classes</a> + </li> + </ol> + </li> + <li> + <a href="#WhatToTest">What To Test</a> + </li> + <li> + <a href="#NextSteps">Next Steps</a> + </li> + </ol> + <h2>Key Classes</h2> + <ol> + <li>{@link android.test.InstrumentationTestRunner}</li> + <li>{@link android.test.ProviderTestCase2}</li> + <li>{@link android.test.IsolatedContext}</li> + <li>{@link android.test.mock.MockContentResolver}</li> + </ol> + <h2>See Also</h2> + <ol> + <li> + <a + href="{@docRoot}guide/topics/testing/topics/testing_android.html"> + Testing Fundamentals</a> + </li> + <li> + <a href="{@docRoot}guide/developing/testing/testing_eclipse.html"> + Testing in Eclipse, with ADT</a> + </li> + <li> + <a href="{@docRoot}guide/developing/testing/testing_otheride.html"> + Testing in Other IDEs</a> + </li> + </ol> + </div> +</div> +<p> + Content providers, which store and retrieve data and make it accessible across applications, + are a key part of the Android API. As an application developer you're allowed to provide your + own public providers for use by other applications. If you do, then you should test them + using the API you publish. +</p> +<p> + This document describes how to test public content providers, although the information is + also applicable to providers that you keep private to your own application. If you aren't + familiar with content providers or the Android testing framework, please read + <a href="{@docRoot}guide/topics/providers/content-providers.html">Content Providers</a>, + the guide to developing content providers, and + <a href="{@docRoot}guide/topics/testing/testing_android.html">Testing Fundamentals</a>, + the introduction to the Android testing and instrumentation framework. +</p> +<h2 id="DesignAndTest">Content Provider Design and Testing</h2> +<p> + In Android, content providers are viewed externally as data APIs that provide + tables of data, with their internals hidden from view. A content provider may have many + public constants, but it usually has few if any public methods and no public variables. + This suggests that you should write your tests based only on the provider's public members. + A content provider that is designed like this is offering a contract between itself and its + users. +</p> +<p> + The base test case class for content providers, + {@link android.test.ProviderTestCase2}, allows you to test your content provider in an + isolated environment. Android mock objects such as {@link android.test.IsolatedContext} and + {@link android.test.mock.MockContentResolver} also help provide an isolated test environment. +</p> +<p> + As with other Android tests, provider test packages are run under the control of the test + runner {@link android.test.InstrumentationTestRunner}. The section + <a href="{@docRoot}guide/topics/testing/testing_android.html#InstrumentationTestRunner"> + Running Tests With InstrumentationTestRunner</a> describes the test runner in + more detail. The topic <a href="{@docRoot}guide/developing/testing/testing_eclipse.html"> + Testing in Eclipse, with ADT</a> shows you how to run a test package in Eclipse, and the + topic <a href="{@docRoot}guide/developing/testing/testing_otheride.html"> + Testing in Other IDEs</a> + shows you how to run a test package from the command line. +</p> +<h2 id="ContentProviderTestAPI">Content Provider Testing API</h2> +<p> + The main focus of the provider testing API is to provide an isolated testing environment. This + ensures that tests always run against data dependencies set explicitly in the test case. It + also prevents tests from modifying actual user data. For example, you want to avoid writing + a test that fails because there was data left over from a previous test, and you want to + avoid adding or deleting contact information in a actual provider. +</p> +<p> + The test case class and mock object classes for provider testing set up this isolated testing + environment for you. +</p> +<h3 id="ProviderTestCase2">ProviderTestCase2</h3> +<p> + You test a provider with a subclass of {@link android.test.ProviderTestCase2}. This base class + extends {@link android.test.AndroidTestCase}, so it provides the JUnit testing framework as well + as Android-specific methods for testing application permissions. The most important + feature of this class is its initialization, which creates the isolated test environment. +</p> +<p> + The initialization is done in the constructor for {@link android.test.ProviderTestCase2}, which + subclasses call in their own constructors. The {@link android.test.ProviderTestCase2} + constructor creates an {@link android.test.IsolatedContext} object that allows file and + database operations but stubs out other interactions with the Android system. + The file and database operations themselves take place in a directory that is local to the + device or emulator and has a special prefix. +</p> +<p> + The constructor then creates a {@link android.test.mock.MockContentResolver} to use as the + resolver for the test. The {@link android.test.mock.MockContentResolver} class is described in + detail in the section + <a href="{@docRoot}guide/topics/testing/test_android#MockObjectClasses">Mock object classes</a>. +</p> +<p> + Lastly, the constructor creates an instance of the provider under test. This is a normal + {@link android.content.ContentProvider} object, but it takes all of its environment information + from the {@link android.test.IsolatedContext}, so it is restricted to + working in the isolated test environment. All of the tests done in the test case class run + against this isolated object. +</p> +<h3 id="MockObjects">Mock object classes</h3> +<p> + {@link android.test.ProviderTestCase2} uses {@link android.test.IsolatedContext} and + {@link android.test.mock.MockContentResolver}, which are standard mock object classes. To + learn more about them, please read + <a href="{@docRoot}guide/topics/testing/test_android#MockObjectClasses"> + Testing Fundamentals</a>. +</p> +<h2 id="WhatToTest">What To Test</h2> +<p> + The topic <a href="{@docRoot}guide/topics/testing/what_to_test.html">What To Test</a> + lists general considerations for testing Android components. + Here are some specific guidelines for testing content providers. +</p> +<ul> + <li> + Test with resolver methods: Even though you can instantiate a provider object in + {@link android.test.ProviderTestCase2}, you should always test with a resolver object + using the appropriate URI. This ensures that you are testing the provider using the same + interaction that a regular application would use. + </li> + <li> + Test a public provider as a contract: If you intent your provider to be public and + available to other applications, you should test it as a contract. This includes + the following ideas: + <ul> + <li> + Test with constants that your provider publicly exposes. For + example, look for constants that refer to column names in one of the provider's + data tables. These should always be constants publicly defined by the provider. + </li> + <li> + Test all the URIs offered by your provider. Your provider may offer several URIs, + each one referring to a different aspect of the data. The + <a href="{@docRoot}resources/samples/NotePad/index.html">Note Pad</a> sample, + for example, features a provider that offers one URI for retrieving a list of notes, + another for retrieving an individual note by it's database ID, and a third for + displaying notes in a live folder. The sample test package for Note Pad, + <a href="{@docRoot}resources/samples/NotePadTest/index.html"> Note Pad Test</a>, has + unit tests for two of these URIs. + </li> + <li> + Test invalid URIs: Your unit tests should deliberately call the provider with an + invalid URI, and look for errors. Good provider design is to throw an + IllegalArgumentException for invalid URIs. + + </li> + </ul> + </li> + <li> + Test the standard provider interactions: Most providers offer six access methods: + query, insert, delete, update, getType, and onCreate(). Your tests should verify that all + of these methods work. These are described in more detail in the topic + <a href="{@docRoot}guide/topics/providers/content-providers.html">Content Providers</a>. + </li> + <li> + Test business logic: Don't forget to test the business logic that your provider should + enforce. Business logic includes handling of invalid values, financial or arithmetic + calculations, elimination or combining of duplicates, and so forth. A content provider + does not have to have business logic, because it may be implemented by activities that + modify the data. If the provider does implement business logic, you should test it. + </li> +</ul> +<h2 id="NextSteps">Next Steps</h2> +<p> + To learn how to set up and run tests in Eclipse, please refer to <a + href="{@docRoot}guide/developing/testing/testing_eclipse.html">Testing in + Eclipse, with ADT</a>. If you're not working in Eclipse, refer to <a + href="{@docRoot}guide/developing/testing/testing_otheride.html">Testing in Other + IDEs</a>. +</p> +<p> + If you want a step-by-step introduction to testing activities, try one of the + testing tutorials: +</p> +<ul> + <li> + The <a + href="{@docRoot}resources/tutorials/testing/helloandroid_test.html">Hello, + Testing</a> tutorial introduces basic testing concepts and procedures in the + context of the Hello, World application. + </li> + <li> + The <a + href="{@docRoot}resources/tutorials/testing/activity_test.html">Activity + Testing</a> tutorial is an excellent follow-up to the Hello, Testing tutorial. + It guides you through a more complex testing scenario that you develop against a + more realistic activity-oriented application. + </li> +</ul> |