Create your first application with Bonita Java APIs
Learn how to set up a Maven client application that uses Bonita Java APIs to communicate with Bonita Engine and run a process.
It assumes that you are a Java programmer familiar with Maven.
Bonita Client APIs
In this example, we use the following APIs:
-
LoginAPI: Manages the login on tenants. Using this API you can obtain an APISession, which is required for access to the tenant APIs, such as the IdentityAPI and the ProcessAPI.
-
ProcessAPI: Manages processes. Using this API you can handle process execution (for example, start a process, retrieve a task, execute a task, or retrieve data) and process management (for example, deploy, undeploy, enable or disable a process).
Maven dependencies
In order to use the client APIs, you need to add a dependency to the bonita-client
artifact in your Maven pom.xml
file:
<properties>
<bonita.bpm.version>7.15.0</bonita.bpm.version>
...
</properties>
<!-- Bonita Engine -->
<dependency>
<groupId>org.bonitasoft.engine</groupId>
<artifactId>bonita-client</artifactId>
<version>${bonita.bpm.version}</version>
</dependency>
<!-- If you use Subscription edition, use this dependency instead: -->
<!--dependency>
<groupId>com.bonitasoft.engine</groupId>
<artifactId>bonita-client-sp</artifactId>
<version>${bonita.bpm.version}</version>
</dependency-->
Configure the connection to the Bonita Platform
You must configure the connection to the Engine (i.e. Bonita Platform) for your project. To do so you can use System properties or programmatic configuration.
Take a look at how to configure a client
Log in
The first action of the client must be to log in. This example shows how to log in when accessing the server over HTTP:
// Let's set the connection settings to use HTTP on the already running Bonita runtime:
Map<String, String> settings = new HashMap<String, String>();
settings.put("server.url", "http://localhost:8080");
settings.put("application.name", "bonita");
// HTTP Basic Auth is active by default on server-side:
settings.put("basicAuthentication.active", "true");
settings.put("basicAuthentication.username", "http-api"); // default value, can be changed server-side in file <BONITA>/server/conf/tomcat-users.xml
settings.put("basicAuthentication.password", "h11p-@p1"); // default value, can be changed server-side in file <BONITA>/server/conf/tomcat-users.xml
APITypeManager.setAPITypeAndParams(ApiAccessType.HTTP, settings);
// First of all, let's log in on the engine:
org.bonitasoft.engine.api.APIClient apiClient = new APIClient();
apiClient.login(username, password); // use "install" / "install" if you don't have any other user created
Example of a client program
In this example, a user interacts with a Bonita process by choosing actions from a command-line client program written in Java.
The user can choose one of the following actions:
-
start a process
-
list open process instances: process instances that have not yet completed
-
list archived process instances: process instances that have completed
-
list pending tasks
-
execute a task
The program displays a menu presented by the getMenutTextContent
method:
private static String getMenutTextContent() {
StringBuilder stb = new StringBuilder("\nChoose the action to be executed:\n");
stb.append("0 - exit\n");
stb.append("1 - start a process\n");
stb.append("2 - list open process instances\n");
stb.append("3 - list archived process instances\n");
stb.append("4 - list pending tasks \n");
stb.append("5 - execute a task\n");
stb.append("Choice:");
return stb.toString();
}
These choices are interpreted by the following code:
private static void executeActions(ProcessDefinition processDefinition)
throws IOException, BonitaException {
String message = getMenutTextContent();
String choice = null;
do {
// show the menu and read the action chosen by the user
choice = readLine(message);
if ("1".equals(choice)) {
// if user chooses 1, start a new process instance
startProcess(processDefinition);
} else if ("2".equals(choice)) {
// if user chooses 2, list open process instances
listOpenedProcessInstances();
} else if ("3".equals(choice)) {
// if user chooses 3, list archived process instances
listArchivedProcessInstances();
} else if ("4".equals(choice)) {
// if user chooses 4, list pending tasks
listPendingTasks();
} else if ("5".equals(choice)) {
// if user chooses 5, execute the task chosen by the user
executeATask();
} else if (!"0".equals(choice)) {
System.out.println("Invalid choice!");
}
} while (!"0".equals(choice));
}
Start a process
private static void startProcess(ProcessDefinition processDefinition) {
ProcessAPI processAPI = apiClient.getProcessAPI();
ProcessInstance processInstance = processAPI.startProcess(processDefinition.getId());
}
List open process instances
All Bonita Java API methods that deal with collections are paged to avoid having too many entries in memory. For these methods, if you want to retrieve all results you need to handle this page by page. This the case with the searchProcessInstances method used here to retrieve open process instances. In the example, each page will contain up to 5 (PAGE_SIZE) elements:
private static void listOpenedProcessInstances() {
// the result will be retrieved by pages of PAGE_SIZE size
int startIndex = 0;
int page = 1;
SearchResult<ProcessInstance> result = null;
do {
// get the current page of open process instances
result = getOpenProcessInstancePage(apiClient, startIndex);
// print the current page
printOpenedProcessIntancesPage(page, result);
// go to next page
startIndex += PAGE_SIZE;
page++;
} while (result.getResult().size() == PAGE_SIZE);
}
private static SearchResult<ProcessInstance> getOpenProcessInstancePage(APIClient apiClient, int startIndex) throws BonitaException {
// create a new SeachOptions with given start index and PAGE_SIZE as max number of elements
SearchOptionsBuilder optionsBuilder = new SearchOptionsBuilder(startIndex, PAGE_SIZE);
// sort the result by the process instance id in ascending order
optionsBuilder.sort(ProcessInstanceSearchDescriptor.ID, Order.ASC);
// perform the request and return the result
ProcessAPI processAPI = apiClient.getProcessAPI();
return processAPI.searchProcessInstances(optionsBuilder.done());
}
List archived process instances
In order to retrieve all archived process instances you also need to iterate page by page:
private static void listArchivedProcessInstances() {
// the result will be retrieved by pages of PAGE_SIZE size
int startIndex = 0;
int page = 1;
SearchResult<ArchivedProcessInstance> result = null;
do {
// get the current page of opened process instances
result = getArchivedProcessInstancePage(apiClient, startIndex);
// print the current page
printArchivedProcessInstancePage(page, result);
// go to the next page
startIndex += PAGE_SIZE;
page++;
} while (result.getResult().size() == PAGE_SIZE);
}
private static SearchResult<ArchivedProcessInstance> getArchivedProcessInstancePage(APIClient apiClient, int startIndex) throws BonitaException {
// create a new SeachOptions with given start index and PAGE_SIZE as max number of elements
SearchOptionsBuilder optionsBuilder = new SearchOptionsBuilder(startIndex, PAGE_SIZE);
// when process instances are archived the original process instance id is supplied by SOURCE_OBJECT_ID,
// so the result will be sort by the SOURCE_OBJECT_ID
optionsBuilder.sort(ArchivedProcessInstancesSearchDescriptor.SOURCE_OBJECT_ID, Order.ASC);
// perform the request and return the result;
ProcessAPI processAPI = apiClient.getProcessAPI();
return processAPI.searchArchivedProcessInstances(optionsBuilder.done());
}
List pending tasks
To get the pending tasks for the logged user, you use the method getPendingHumanTaskInstances.
private static void listPendingTasks() {
ProcessAPI processAPI = apiClient.getProcessAPI();
// the result will be retrieved by pages of PAGE_SIZE size
int startIndex = 0;
int page = 1;
List<HumanTaskInstance> pendingTasks = null;
do {
// get the current page
pendingTasks = processAPI.getPendingHumanTaskInstances(session.getUserId(), startIndex, PAGE_SIZE, ActivityInstanceCriterion.LAST_UPDATE_ASC);
// print the current page
printTasksPage(page, pendingTasks);
// got to next page
startIndex += PAGE_SIZE;
page++;
} while (pendingTasks.size() == PAGE_SIZE);
}
Execute a task
Before a user can execute a task, the task needs to be assigned to the user. The assignUserTask method assigns the task to the user. The executeFlowNode method executes the task.
private static void executeATask() {
processAPI.assignUserTask(taskToExecute.getId(), session.getUserId());
processAPI.executeFlowNode(taskToExecute.getId());
}