Author: mibo
Date: Tue Apr 28 11:41:47 2015
New Revision: 1676498
URL: http://svn.apache.org/r1676498
Log:
CMS commit to olingo by mibo
Modified:
olingo/site/trunk/content/doc/odata4/tutorials/read/tutorial_read.mdtext
Modified:
olingo/site/trunk/content/doc/odata4/tutorials/read/tutorial_read.mdtext
URL:
http://svn.apache.org/viewvc/olingo/site/trunk/content/doc/odata4/tutorials/read/tutorial_read.mdtext?rev=1676498&r1=1676497&r2=1676498&view=diff
==============================================================================
--- olingo/site/trunk/content/doc/odata4/tutorials/read/tutorial_read.mdtext
(original)
+++ olingo/site/trunk/content/doc/odata4/tutorials/read/tutorial_read.mdtext
Tue Apr 28 11:41:47 2015
@@ -355,21 +355,20 @@ Letâs have a closer look at the met
First, we need to declare some constants, to be used in below code
-```java
-// Service Namespace
-public static final String NAMESPACE = "com.example.model";
-
-// EDM Container
-public static final String CONTAINER_NAME = "Container";
-public static final FullQualifiedName CONTAINER = new
FullQualifiedName(NAMESPACE, CONTAINER_NAME);
-
-// Entity Types Names
-public static final String ET_PRODUCT_NAME = "Product";
-public static final FullQualifiedName ET_PRODUCT_FQN = new
FullQualifiedName(NAMESPACE, ET_PRODUCT_NAME);
-
-// Entity Set Names
-public static final String ES_PRODUCTS_NAME = "Products";
-```
+ // Service Namespace
+ public static final String NAMESPACE = "com.example.model";
+
+ // EDM Container
+ public static final String CONTAINER_NAME = "Container";
+ public static final FullQualifiedName CONTAINER = new
FullQualifiedName(NAMESPACE, CONTAINER_NAME);
+
+ // Entity Types Names
+ public static final String ET_PRODUCT_NAME = "Product";
+ public static final FullQualifiedName ET_PRODUCT_FQN = new
FullQualifiedName(NAMESPACE, ET_PRODUCT_NAME);
+
+ // Entity Set Names
+ public static final String ES_PRODUCTS_NAME = "Products";
+
**_getEntityType()_**
@@ -385,34 +384,32 @@ The properties: name and type and additi
Which of the properties is the âkeyâ property: a reference to the âIDâ
property.
-```java
-@Override
-public EntityType getEntityType(FullQualifiedName entityTypeName) throws
ODataException {
-
- // this method is called for one of the EntityTypes that are configured
in the Schema
- if(entityTypeName.equals(ET_PRODUCT_FQN)){
-
- //create EntityType properties
- Property id = new
Property().setName("ID").setType(EdmPrimitiveTypeKind.Int32.getFullQualifiedName());
- Property name = new
Property().setName("Name").setType(EdmPrimitiveTypeKind.String.getFullQualifiedName());
- Property description = new
Property().setName("Description").setType(EdmPrimitiveTypeKind.String.getFullQualifiedName());
-
- // create PropertyRef for Key element
- PropertyRef propertyRef = new PropertyRef();
- propertyRef.setPropertyName("ID");
-
- // configure EntityType
- EntityType entityType = new EntityType();
- entityType.setName(ET_PRODUCT_NAME);
- entityType.setProperties(Arrays.asList(id, name , description));
- entityType.setKey(Arrays.asList(propertyRef));
-
- return entityType;
- }
-
- return null;
-}
-```
+ @Override
+ public EntityType getEntityType(FullQualifiedName entityTypeName) throws
ODataException {
+
+ // this method is called for one of the EntityTypes that are configured
in the Schema
+ if(entityTypeName.equals(ET_PRODUCT_FQN)){
+
+ //create EntityType properties
+ Property id = new
Property().setName("ID").setType(EdmPrimitiveTypeKind.Int32.getFullQualifiedName());
+ Property name = new
Property().setName("Name").setType(EdmPrimitiveTypeKind.String.getFullQualifiedName());
+ Property description = new
Property().setName("Description").setType(EdmPrimitiveTypeKind.String.getFullQualifiedName());
+
+ // create PropertyRef for Key element
+ PropertyRef propertyRef = new PropertyRef();
+ propertyRef.setPropertyName("ID");
+
+ // configure EntityType
+ EntityType entityType = new EntityType();
+ entityType.setName(ET_PRODUCT_NAME);
+ entityType.setProperties(Arrays.asList(id, name , description));
+ entityType.setKey(Arrays.asList(propertyRef));
+
+ return entityType;
+ }
+
+ return null;
+ }
**_getEntitySet()_**
@@ -420,29 +417,29 @@ public EntityType getEntityType(FullQual
The procedure for declaring the _EntitySets_ is similar.
An _EntitySet_ is a crucial resource, when an OData service is used to request
data.
In our example, weâll invoke the following URL, which we expect to provide
us a list of products:
-```html
-http://localhost:8080/DemoService/DemoServlet.svc/Products
-```
+
+ http://localhost:8080/DemoService/DemoServlet.svc/Products
+
When declaring an _EntitySet_, we need to define the type of entries which are
contained in the list. Such type is an _EntityType_.
In our example, we set our previously created _EntityType_, which is referred
by a _FullQualifiedName_.
-```java
-@Override
-public EntitySet getEntitySet(FullQualifiedName entityContainer, String
entitySetName) throws ODataException {
-
- if(entityContainer.equals(CONTAINER)){
- if(entitySetName.equals(ES_PRODUCTS_NAME)){
- EntitySet entitySet = new EntitySet();
- entitySet.setName(ES_PRODUCTS_NAME);
- entitySet.setType(ET_PRODUCT_FQN);
-
- return entitySet;
- }
- }
-
- return null;
-}
-```
+
+ @Override
+ public EntitySet getEntitySet(FullQualifiedName entityContainer, String
entitySetName) throws ODataException {
+
+ if(entityContainer.equals(CONTAINER)){
+ if(entitySetName.equals(ES_PRODUCTS_NAME)){
+ EntitySet entitySet = new EntitySet();
+ entitySet.setName(ES_PRODUCTS_NAME);
+ entitySet.setType(ET_PRODUCT_FQN);
+
+ return entitySet;
+ }
+ }
+
+ return null;
+ }
+
**_getEntityContainer()_**
@@ -450,22 +447,21 @@ public EntitySet getEntitySet(FullQualif
In order to provide data, our OData service needs an _EntityContainer_ that
carries the _EntitySets_.
In our example, we have only one _EntitySet_, so we create one
_EntityContainer_ and set our _EntitySet_.
-```java
-@Override
-public EntityContainer getEntityContainer() throws ODataException {
-
- // create EntitySets
- List<EntitySet> entitySets = new ArrayList<EntitySet>();
- entitySets.add(getEntitySet(CONTAINER, ES_PRODUCTS_NAME));
-
- // create EntityContainer
- EntityContainer entityContainer = new EntityContainer();
- entityContainer.setName(CONTAINER_NAME);
- entityContainer.setEntitySets(entitySets);
-
- return entityContainer;
-}
-```
+
+ @Override
+ public EntityContainer getEntityContainer() throws ODataException {
+
+ // create EntitySets
+ List<EntitySet> entitySets = new ArrayList<EntitySet>();
+ entitySets.add(getEntitySet(CONTAINER, ES_PRODUCTS_NAME));
+
+ // create EntityContainer
+ EntityContainer entityContainer = new EntityContainer();
+ entityContainer.setName(CONTAINER_NAME);
+ entityContainer.setEntitySets(entitySets);
+
+ return entityContainer;
+ }
**_getSchemas()_**
@@ -477,47 +473,46 @@ So, in our example, we create a list of
The schema is configured with a _Namespace_, which serves to uniquely identify
all elements.
Then our elements are added to the Schema.
-```java
-@Override
-public List<Schema> getSchemas() throws ODataException {
-
- // create Schema
- Schema schema = new Schema();
- schema.setNamespace(NAMESPACE);
-
- // add EntityTypes
- List<EntityType> entityTypes = new ArrayList<EntityType>();
- entityTypes.add(getEntityType(ET_PRODUCT_FQN));
- schema.setEntityTypes(entityTypes);
-
- // add EntityContainer
- schema.setEntityContainer(getEntityContainer());
-
- // finally
- List<Schema> schemas = new ArrayList<Schema>();
- schemas.add(schema);
-
- return schemas;
-}
-```
+
+ @Override
+ public List<Schema> getSchemas() throws ODataException {
+
+ // create Schema
+ Schema schema = new Schema();
+ schema.setNamespace(NAMESPACE);
+
+ // add EntityTypes
+ List<EntityType> entityTypes = new ArrayList<EntityType>();
+ entityTypes.add(getEntityType(ET_PRODUCT_FQN));
+ schema.setEntityTypes(entityTypes);
+
+ // add EntityContainer
+ schema.setEntityContainer(getEntityContainer());
+
+ // finally
+ List<Schema> schemas = new ArrayList<Schema>();
+ schemas.add(schema);
+
+ return schemas;
+ }
**_getEntityContainerInfo()_**
-```java
-@Override
-public EntityContainerInfo getEntityContainerInfo(FullQualifiedName
entityContainerName) throws ODataException {
-
-// This method is invoked when displaying the service document at e.g.
http://localhost:8080/DemoService/DemoService.svc
- if(entityContainerName == null ||
entityContainerName.equals(CONTAINER)){
- EntityContainerInfo entityContainerInfo = new
EntityContainerInfo();
- entityContainerInfo.setContainerName(CONTAINER);
- return entityContainerInfo;
- }
-
- return null;
-}
-```
+
+ @Override
+ public EntityContainerInfo getEntityContainerInfo(FullQualifiedName
entityContainerName) throws ODataException {
+
+ // This method is invoked when displaying the service document at e.g.
http://localhost:8080/DemoService/DemoService.svc
+ if(entityContainerName == null ||
entityContainerName.equals(CONTAINER)){
+ EntityContainerInfo entityContainerInfo = new
EntityContainerInfo();
+ entityContainerInfo.setContainerName(CONTAINER);
+ return entityContainerInfo;
+ }
+
+ return null;
+ }
+
**Summary:**
We have created a class that declares the metadata of our OData service.
@@ -526,46 +521,46 @@ We have declared the main elements of an
At runtime of an OData service, such metadata can be viewed by invoking the
Metadata Document.
In our example:
-```
-http://localhost:8080/DemoService/DemoService.svc/$metadata
-```
-
-```xml
-<?xml version='1.0' encoding='UTF-8'?>
-<edmx:Edmx Version="4.0" xmlns:edmx="http://docs.oasis-open.org/odata/ns/edmx";>
- <edmx:DataServices>
- <Schema xmlns="http://docs.oasis-open.org/odata/ns/edm";
Namespace="com.example.model">
- <EntityType Name="Product">
- <Key>
- <PropertyRef Name="ID"/>
- </Key>
- <Property Name="ID" Type="Edm.Int32"/>
- <Property Name="Name" Type="Edm.String"/>
- <Property Name="Description" Type="Edm.String"/>
- </EntityType>
- <EntityContainer Name="Container">
- <EntitySet Name="Products" EntityType="com.example.model.Product"/>
- </EntityContainer>
- </Schema>
- </edmx:DataServices>
-</edmx:Edmx>
-```
+
+ http://localhost:8080/DemoService/DemoService.svc/$metadata
+
+
+
+ <?xml version='1.0' encoding='UTF-8'?>
+ <edmx:Edmx Version="4.0"
xmlns:edmx="http://docs.oasis-open.org/odata/ns/edmx";>
+ <edmx:DataServices>
+ <Schema xmlns="http://docs.oasis-open.org/odata/ns/edm";
Namespace="com.example.model">
+ <EntityType Name="Product">
+ <Key>
+ <PropertyRef Name="ID"/>
+ </Key>
+ <Property Name="ID" Type="Edm.Int32"/>
+ <Property Name="Name" Type="Edm.String"/>
+ <Property Name="Description" Type="Edm.String"/>
+ </EntityType>
+ <EntityContainer Name="Container">
+ <EntitySet Name="Products" EntityType="com.example.model.Product"/>
+ </EntityContainer>
+ </Schema>
+ </edmx:DataServices>
+ </edmx:Edmx>
+
The Service Document can be invoked to view the Entity Sets, like in our
example at
-```
-http://localhost:8080/DemoService/DemoService.svc/
-```
-
-```json
-{
- "@odata.context" :
"http://localhost:8080/DemoService/DemoService.svc/$metadata";,
- "value" : [
- {
- "name" : "Products",
- "url" : "Products"
- } ]
-}
-```
+
+ http://localhost:8080/DemoService/DemoService.svc/
+
+
+
+ {
+ "@odata.context" :
"http://localhost:8080/DemoService/DemoService.svc/$metadata";,
+ "value" : [
+ {
+ "name" : "Products",
+ "url" : "Products"
+ } ]
+ }
+
> Note:
> After implementing the _EdmProvider_, we can, as an intermediate step,
> build/deploy the service and invoke the 2 static pages: service document
> and metadata document.
@@ -621,9 +616,10 @@ Within our package _myservice.mynamespac
### 4.2.3. Implement the required methods
After creation of the Java class, we can see that there are 2 methods to be
implemented:
-* _init()_
- This method is invoked by the _Olingo_ Framework, allowing us to store
the context object
-* _readEntityCollection()_
+
+ * _init()_
+ This method is invoked by the _Olingo_ Framework, allowing us to
store the context object
+ * _readEntityCollection()_
Here we have to fetch the required data and pass it back to the _Olingo_
FWK
@@ -637,17 +633,16 @@ The _Olingo_ framework initializes the p
According to the Javadoc, this object is the âRoot object for serving
factory tasksâ¦â
Weâll need it later, so we store it as member variable.
-```java
- public void init(OData odata, ServiceMetadata serviceMetadata) {
- this.odata = odata;
- }
-```
+
+ public void init(OData odata, ServiceMetadata serviceMetadata) {
+ this.odata = odata;
+ }
+
Donât forget to declare the member variable
-```java
- private OData odata;
-```
+
+ private OData odata;
**_readEntityCollection()_**
@@ -695,56 +690,55 @@ Because the _readEntityCollection_ metho
The steps for implementating the method _readEntityCollection_ are:
-1. Which data is requested?
-Usually, an OData service provides different _EntitySets_, so first it is
required to identify which _EntitySet_ has been requested. This information can
be retrieved from the _uriInfo_ object
-
-2. Fetch the data
-As a developer of the OData service, you have to know how and where the data
is stored. In many cases, this would be a database. At this point, you would
connect to your database and fetch the requested data with an appropriate SQL
statement. The data that is fetched from the data storage has to be put into an
_EntitySet_ object.
-Note that this object has to be of type _EntitySet_, not _EdmEntitySet_
-The package _org.apache.olingo.commons.api.data_ provides interfaces that
describe the actual data, not the metadata.
+ 1. Which data is requested?
+ Usually, an OData service provides different _EntitySets_, so first it is
required to identify which _EntitySet_ has been requested. This information can
be retrieved from the _uriInfo_ object
+ 2. Fetch the data
+ As a developer of the OData service, you have to know how and where the data
is stored. In many cases, this would be a database. At this point, you would
connect to your database and fetch the requested data with an appropriate SQL
statement. The data that is fetched from the data storage has to be put into an
_EntitySet_ object.
+ Note that this object has to be of type _EntitySet_, not _EdmEntitySet_
+ The package _org.apache.olingo.commons.api.data_ provides interfaces that
describe the actual data, not the metadata.
-3. Transform the data
-_Olingo_ expects from us to provide the data as low-level _InputStream_
object. However, _Olingo_ supports us in doing so, by providing us with a
proper "serializer".
-So what we have to do is create the serializer based on the requested content
type, configure it and call it.
+ 3. Transform the data
+ _Olingo_ expects from us to provide the data as low-level _InputStream_
object. However, _Olingo_ supports us in doing so, by providing us with a
proper "serializer".
+ So what we have to do is create the serializer based on the requested
content type, configure it and call it.
+
+ 4. Configure the response
+ The response object has been passed to us in the method signature. We use it
to set the serialized data (the _InputStream_ object).
+ Furthermore, we have to set the HTTP status code, which means that we have
the opportunity to do proper error handling.
+ And finally we have to set the content type.
+
+
+ public void readEntityCollection(ODataRequest request, ODataResponse
response, UriInfo uriInfo, ContentType responseFormat)
+ throws ODataApplicationException, SerializerException
{
+
+ // 1st retrieve the requested EntitySet from the uriInfo
(representation of the parsed URI)
+ List<UriResource> resourcePaths = uriInfo.getUriResourceParts();
+ // in our example, the first segment is the EntitySet:
+ UriResourceEntitySet uriResourceEntitySet = (UriResourceEntitySet)
resourcePaths.get(0);
+ EdmEntitySet edmEntitySet = uriResourceEntitySet.getEntitySet();
+
+ // 2nd: fetch the data from backend for this requested EntitySetName
and delivere as EntitySet
+ EntitySet entitySet = getData(edmEntitySet);
+
+ // 3rd: create a serializer based on the requested format (json)
+ ODataFormat format = ODataFormat.fromContentType(responseFormat);
+ ODataSerializer serializer = odata.createSerializer(format);
+
+ // and serialize the content: transform from the EntitySet object to
InputStream
+ EdmEntityType edmEntityType = edmEntitySet.getEntityType();
+ ContextURL contextUrl =
ContextURL.with().entitySet(edmEntitySet).build();
+
+ EntityCollectionSerializerOptions opts =
+
EntityCollectionSerializerOptions.with().contextURL(contextUrl).build();
+ InputStream serializedContent =
serializer.entityCollection(edmEntityType, entitySet, opts);
+
+ // 4th: configure the response object: set the body, headers and status
code
+ response.setContent(serializedContent);
+ response.setStatusCode(HttpStatusCode.OK.getStatusCode());
+ response.setHeader(HttpHeader.CONTENT_TYPE,
responseFormat.toContentTypeString());
+ }
-4. Configure the response
-The response object has been passed to us in the method signature. We use it
to set the serialized data (the _InputStream_ object).
-Furthermore, we have to set the HTTP status code, which means that we have the
opportunity to do proper error handling.
-And finally we have to set the content type.
-
-```java
-public void readEntityCollection(ODataRequest request, ODataResponse response,
UriInfo uriInfo, ContentType responseFormat)
- throws ODataApplicationException, SerializerException {
-
- // 1st retrieve the requested EntitySet from the uriInfo
(representation of the parsed URI)
- List<UriResource> resourcePaths = uriInfo.getUriResourceParts();
- // in our example, the first segment is the EntitySet:
- UriResourceEntitySet uriResourceEntitySet = (UriResourceEntitySet)
resourcePaths.get(0);
- EdmEntitySet edmEntitySet = uriResourceEntitySet.getEntitySet();
-
- // 2nd: fetch the data from backend for this requested EntitySetName
and delivere as EntitySet
- EntitySet entitySet = getData(edmEntitySet);
-
- // 3rd: create a serializer based on the requested format (json)
- ODataFormat format = ODataFormat.fromContentType(responseFormat);
- ODataSerializer serializer = odata.createSerializer(format);
-
- // and serialize the content: transform from the EntitySet object to
InputStream
- EdmEntityType edmEntityType = edmEntitySet.getEntityType();
- ContextURL contextUrl =
ContextURL.with().entitySet(edmEntitySet).build();
-
- EntityCollectionSerializerOptions opts =
-
EntityCollectionSerializerOptions.with().contextURL(contextUrl).build();
- InputStream serializedContent =
serializer.entityCollection(edmEntityType, entitySet, opts);
-
- // 4th: configure the response object: set the body, headers and status
code
- response.setContent(serializedContent);
- response.setStatusCode(HttpStatusCode.OK.getStatusCode());
- response.setHeader(HttpHeader.CONTENT_TYPE,
responseFormat.toContentTypeString());
-}
-```
**_getData()_**
@@ -753,30 +747,29 @@ In our tutorial, to keep the code as sim
Since weâre supposed to deliver the data inside an _EntitySet_ instance, we
create the instance, ask it for the (initially empty) list of entities and add
some new entities to it.
We create the entities and their properties according to what we declared in
our _ExampleEdmProvider_ class. So we have to take care to provide the correct
names to the new property objects.
-```java
-private EntitySet getData(EdmEntitySet edmEntitySet){
- EntitySet entitySet = new EntitySetImpl();
- List<Entity> entityList = entitySet.getEntities();
+ private EntitySet getData(EdmEntitySet edmEntitySet){
+
+ EntitySet entitySet = new EntitySetImpl();
+ List<Entity> entityList = entitySet.getEntities();
- // add some sample product entities
- entityList.add(new EntityImpl()
- .addProperty(new PropertyImpl(null, "ID", ValueType.PRIMITIVE,
1))
- .addProperty(new PropertyImpl(null, "Name",
ValueType.PRIMITIVE, "Notebook Basic 15"))
- .addProperty(new PropertyImpl(null, "Description",
ValueType.PRIMITIVE, "Notebook Basic, 1.7GHz - 15 XGA - 1024MB DDR2 SDRAM -
40GB")));
- entityList.add(new EntityImpl()
- .addProperty(new PropertyImpl(null, "ID", ValueType.PRIMITIVE,
2))
- .addProperty(new PropertyImpl(null, "Name",
ValueType.PRIMITIVE, "1UMTS PDA"))
- .addProperty(new PropertyImpl(null, "Description",
ValueType.PRIMITIVE, "Ultrafast 3G UMTS/HSDPA Pocket PC, supports GSM
network")));
-
- entityList.add(new EntityImpl()
- .addProperty(new PropertyImpl(null, "ID", ValueType.PRIMITIVE,
3))
- .addProperty(new PropertyImpl(null, "Name",
ValueType.PRIMITIVE, "Ergo Screen"))
- .addProperty(new PropertyImpl(null, "Description",
ValueType.PRIMITIVE, "17 Optimum Resolution 1024 x 768 @ 85Hz, resolution 1280
x 960")));
-
- return entitySet;
-}
-```
+ // add some sample product entities
+ entityList.add(new EntityImpl()
+ .addProperty(new PropertyImpl(null, "ID", ValueType.PRIMITIVE,
1))
+ .addProperty(new PropertyImpl(null, "Name",
ValueType.PRIMITIVE, "Notebook Basic 15"))
+ .addProperty(new PropertyImpl(null, "Description",
ValueType.PRIMITIVE, "Notebook Basic, 1.7GHz - 15 XGA - 1024MB DDR2 SDRAM -
40GB")));
+ entityList.add(new EntityImpl()
+ .addProperty(new PropertyImpl(null, "ID", ValueType.PRIMITIVE,
2))
+ .addProperty(new PropertyImpl(null, "Name",
ValueType.PRIMITIVE, "1UMTS PDA"))
+ .addProperty(new PropertyImpl(null, "Description",
ValueType.PRIMITIVE, "Ultrafast 3G UMTS/HSDPA Pocket PC, supports GSM
network")));
+
+ entityList.add(new EntityImpl()
+ .addProperty(new PropertyImpl(null, "ID", ValueType.PRIMITIVE,
3))
+ .addProperty(new PropertyImpl(null, "Name",
ValueType.PRIMITIVE, "Ergo Screen"))
+ .addProperty(new PropertyImpl(null, "Description",
ValueType.PRIMITIVE, "17 Optimum Resolution 1024 x 768 @ 85Hz, resolution 1280
x 960")));
+
+ return entitySet;
+ }
@@ -808,36 +801,35 @@ Furthermore, the _ODataHttpHandler_ need
As such, hereâs the location where our 2 implemented classes come together,
the metadata declaration and the data provisioning.
-```java
-// This class represents a standard HttpServlet implementation.
-// It is used as main entry point for the web application that carries the
OData service.
-// The implementation of this HttpServlet simply delegates the user requests
to the ODataHttpHandler
-public class DemoServlet extends HttpServlet {
-
- private static final long serialVersionUID = 1L;
- private static final Logger LOG =
LoggerFactory.getLogger(DemoServlet.class);
-
- @Override
- protected void service(final HttpServletRequest req, final
HttpServletResponse resp) throws ServletException, IOException {
-
- try {
- // create odata handler and configure it with
EdmProvider and Processor
- OData odata = OData.newInstance();
- ServiceMetadata edm = odata.createServiceMetadata(new
ExampleEdmProvider(), new ArrayList<EdmxReference>());
- ODataHttpHandler handler = odata.createHandler(edm);
- handler.register(new DemoEntityCollectionProcessor());
-
- // let the handler do the work
- handler.process(req, resp);
-
- } catch (RuntimeException e) {
- LOG.error("Server Error ocurred in DemoServlet", e);
- throw new ServletException(e);
- }
- }
-}
-```
+ // This class represents a standard HttpServlet implementation.
+ // It is used as main entry point for the web application that carries the
OData service.
+ // The implementation of this HttpServlet simply delegates the user
requests to the ODataHttpHandler
+ public class DemoServlet extends HttpServlet {
+
+ private static final long serialVersionUID = 1L;
+ private static final Logger LOG =
LoggerFactory.getLogger(DemoServlet.class);
+
+ @Override
+ protected void service(final HttpServletRequest req, final
HttpServletResponse resp) throws ServletException, IOException {
+
+ try {
+ // create odata handler and configure it with
EdmProvider and Processor
+ OData odata = OData.newInstance();
+ ServiceMetadata edm = odata.createServiceMetadata(new
ExampleEdmProvider(), new ArrayList<EdmxReference>());
+ ODataHttpHandler handler = odata.createHandler(edm);
+ handler.register(new DemoEntityCollectionProcessor());
+
+ // let the handler do the work
+ handler.process(req, resp);
+
+ } catch (RuntimeException e) {
+ LOG.error("Server Error ocurred in DemoServlet", e);
+ throw new ServletException(e);
+ }
+ }
+ }
+
### 4.3.2. Edit the web.xml
@@ -847,26 +839,25 @@ Furthermore, we need to specify the _url
Open the _src/main/webapp/WEB-INF/web.xml_ file and paste the following
content into it:
-```xml
-<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance";
- xmlns="http://java.sun.com/xml/ns/javaee";
- xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd";
- xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd";
- id="WebApp_ID" version="2.5">
-
-<servlet>
- <servlet-name>DemoServlet</servlet-name>
- <servlet-class> myservice.mynamespace.web.DemoServlet</servlet-class>
- <load-on-startup>1</load-on-startup>
-</servlet>
-
-<servlet-mapping>
- <servlet-name>DemoServlet</servlet-name>
- <url-pattern>/DemoService.svc/*</url-pattern>
-</servlet-mapping>
-</web-app>
-```
+ <web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance";
+ xmlns="http://java.sun.com/xml/ns/javaee";
+ xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd";
+ xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd";
+ id="WebApp_ID" version="2.5">
+
+ <servlet>
+ <servlet-name>DemoServlet</servlet-name>
+ <servlet-class> myservice.mynamespace.web.DemoServlet</servlet-class>
+ <load-on-startup>1</load-on-startup>
+ </servlet>
+
+ <servlet-mapping>
+ <servlet-name>DemoServlet</servlet-name>
+ <url-pattern>/DemoService.svc/*</url-pattern>
+ </servlet-mapping>
+ </web-app>
+
Thatâs it. Now we can build and run the web application.
@@ -905,78 +896,77 @@ Try the following URLs:
**Service Document**
-```
-http://localhost:8080/DemoService/DemoService.svc/
-```
+ http://localhost:8080/DemoService/DemoService.svc/
+
The expected result is the service document which displays our
_EntityContainerInfo_:
-```json
-{
- "@odata.context" :
"http://localhost:8080/DemoService/DemoService.svc/$metadata";,
- "value" : [
- {
- "name" : "Products",
- "url" : "Products"
- } ]
-}
-```
+
+ {
+ "@odata.context" :
"http://localhost:8080/DemoService/DemoService.svc/$metadata";,
+ "value" : [
+ {
+ "name" : "Products",
+ "url" : "Products"
+ } ]
+ }
+
**Metadata Document**
-```
-http://localhost:8080/ExampleService1/ExampleService1.svc/$metadata
-```
+
+ http://localhost:8080/ExampleService1/ExampleService1.svc/$metadata
+
The expected result is the metadata document that displays our _Schema_,
_EntityType_, _EntityContainer_ and _EntitySet_.
-```xml
-<?xml version='1.0' encoding='UTF-8'?>
-<edmx:Edmx Version="4.0" xmlns:edmx="http://docs.oasis-open.org/odata/ns/edmx";>
- <edmx:DataServices>
- <Schema xmlns="http://docs.oasis-open.org/odata/ns/edm";
Namespace="com.example.model">
- <EntityType Name="Product">
- <Key>
- <PropertyRef Name="ID"/>
- </Key>
- <Property Name="ID" Type="Edm.Int32"/>
- <Property Name="Name" Type="Edm.String"/>
- <Property Name="Description" Type="Edm.String"/>
- </EntityType>
- <EntityContainer Name="Container">
- <EntitySet Name="Products" EntityType="com.example.model.Product"/>
- </EntityContainer>
- </Schema>
- </edmx:DataServices>
-</edmx:Edmx>
-```
+
+ <?xml version='1.0' encoding='UTF-8'?>
+ <edmx:Edmx Version="4.0"
xmlns:edmx="http://docs.oasis-open.org/odata/ns/edmx";>
+ <edmx:DataServices>
+ <Schema xmlns="http://docs.oasis-open.org/odata/ns/edm";
Namespace="com.example.model">
+ <EntityType Name="Product">
+ <Key>
+ <PropertyRef Name="ID"/>
+ </Key>
+ <Property Name="ID" Type="Edm.Int32"/>
+ <Property Name="Name" Type="Edm.String"/>
+ <Property Name="Description" Type="Edm.String"/>
+ </EntityType>
+ <EntityContainer Name="Container">
+ <EntitySet Name="Products" EntityType="com.example.model.Product"/>
+ </EntityContainer>
+ </Schema>
+ </edmx:DataServices>
+ </edmx:Edmx>
+
**Query / EntitySet**
-```
-http://localhost:8080/DemoService/DemoService.svc/Products
-```
+
+ http://localhost:8080/DemoService/DemoService.svc/Products
+
The expected result is the hardcoded list of product entries, which we have
coded in our processor implementation:
-```json
-{
- "@odata.context":"$metadata#Products","
- value":[
- {
- "ID":1,
- "Name":"Notebook Basic 15",
- "Description":"Notebook Basic, 1.7GHz - 15 XGA - 1024MB DDR2 SDRAM -
40GB"
- },
- {
- "ID":2,
- "Name":"1UMTS PDA",
- "Description":"Ultrafast 3G UMTS/HSDPA Pocket PC, supports GSM network"
- },
+
{
- "ID":3,
- "Name":"Ergo Screen",
- "Description":"17 Optimum Resolution 1024 x 768 @ 85Hz, resolution 1280
x 960"
- }]
-}
-```
+ "@odata.context":"$metadata#Products","
+ value":[
+ {
+ "ID":1,
+ "Name":"Notebook Basic 15",
+ "Description":"Notebook Basic, 1.7GHz - 15 XGA - 1024MB DDR2 SDRAM -
40GB"
+ },
+ {
+ "ID":2,
+ "Name":"1UMTS PDA",
+ "Description":"Ultrafast 3G UMTS/HSDPA Pocket PC, supports GSM
network"
+ },
+ {
+ "ID":3,
+ "Name":"Ergo Screen",
+ "Description":"17 Optimum Resolution 1024 x 768 @ 85Hz, resolution
1280 x 960"
+ }]
+ }
+
---
