这是目录结构
这是activiti.cfg.xml
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd">
<bean id="processEngineConfiguration" class="org.activiti.engine.impl.cfg.StandaloneProcessEngineConfiguration">
<property name="jdbcDriver" value="com.mysql.jdbc.Driver" />
<property name="jdbcUrl" value="jdbc:mysql://127.0.0.1:3306/mydb" />
<property name="jdbcUsername" value="root" />
<property name="jdbcPassword" value="zxt0txz" />
<property name="databaseSchemaUpdate" value="true" />
</bean>
</beans>
这是bpmn文件
<?xml version="1.0" encoding="UTF-8"?>
<definitions xmlns="http://www.omg.org/spec/BPMN/20100524/MODEL" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:activiti="http://activiti.org/bpmn" xmlns:bpmndi="http://www.omg.org/spec/BPMN/20100524/DI" xmlns:omgdc="http://www.omg.org/spec/DD/20100524/DC" xmlns:omgdi="http://www.omg.org/spec/DD/20100524/DI" typeLanguage="http://www.w3.org/2001/XMLSchema" expressionLanguage="http://www.w3.org/1999/XPath" targetNamespace="http://www.activiti.org/test">
<process id="myProcess" name="My process" isExecutable="true">
<startEvent id="startevent1" name="Start"></startEvent>
<sequenceFlow id="flow1" sourceRef="startevent1" targetRef="usertask3"></sequenceFlow>
<userTask id="usertask2" name="Handle Request"></userTask>
<sequenceFlow id="flow2" sourceRef="usertask3" targetRef="usertask2"></sequenceFlow>
<userTask id="usertask3" name="Expense Request"></userTask>
<endEvent id="endevent1" name="End"></endEvent>
<sequenceFlow id="flow3" sourceRef="usertask2" targetRef="endevent1"></sequenceFlow>
</process>
<bpmndi:BPMNDiagram id="BPMNDiagram_myProcess">
<bpmndi:BPMNPlane bpmnElement="myProcess" id="BPMNPlane_myProcess">
<bpmndi:BPMNShape bpmnElement="startevent1" id="BPMNShape_startevent1">
<omgdc:Bounds height="35.0" width="35.0" x="180.0" y="200.0"></omgdc:Bounds>
</bpmndi:BPMNShape>
<bpmndi:BPMNShape bpmnElement="usertask2" id="BPMNShape_usertask2">
<omgdc:Bounds height="55.0" width="105.0" x="500.0" y="190.0"></omgdc:Bounds>
</bpmndi:BPMNShape>
<bpmndi:BPMNShape bpmnElement="usertask3" id="BPMNShape_usertask3">
<omgdc:Bounds height="55.0" width="105.0" x="300.0" y="190.0"></omgdc:Bounds>
</bpmndi:BPMNShape>
<bpmndi:BPMNShape bpmnElement="endevent1" id="BPMNShape_endevent1">
<omgdc:Bounds height="35.0" width="35.0" x="740.0" y="200.0"></omgdc:Bounds>
</bpmndi:BPMNShape>
<bpmndi:BPMNEdge bpmnElement="flow1" id="BPMNEdge_flow1">
<omgdi:waypoint x="215.0" y="217.0"></omgdi:waypoint>
<omgdi:waypoint x="300.0" y="217.0"></omgdi:waypoint>
</bpmndi:BPMNEdge>
<bpmndi:BPMNEdge bpmnElement="flow2" id="BPMNEdge_flow2">
<omgdi:waypoint x="405.0" y="217.0"></omgdi:waypoint>
<omgdi:waypoint x="500.0" y="217.0"></omgdi:waypoint>
</bpmndi:BPMNEdge>
<bpmndi:BPMNEdge bpmnElement="flow3" id="BPMNEdge_flow3">
<omgdi:waypoint x="605.0" y="217.0"></omgdi:waypoint>
<omgdi:waypoint x="740.0" y="217.0"></omgdi:waypoint>
</bpmndi:BPMNEdge>
</bpmndi:BPMNPlane>
</bpmndi:BPMNDiagram>
</definitions>
这是流程调用类
package org.start.main;
import org.activiti.engine.ProcessEngine;
import org.activiti.engine.ProcessEngines;
import org.activiti.engine.RepositoryService;
import org.activiti.engine.RuntimeService;
import org.activiti.engine.TaskService;
import org.activiti.engine.task.Task;
public class Main {
public static void main(String[] args) {
ProcessEngine processEngine = ProcessEngines.getDefaultProcessEngine();
RepositoryService repositoryService = processEngine.getRepositoryService();
RuntimeService runtimeService = processEngine.getRuntimeService();
TaskService taskService = processEngine.getTaskService();
repositoryService.createDeployment().addClasspathResource("bpmn/main.bpmn");
runtimeService.startProcessInstanceById("myProcess");
Task taskA = taskService.createTaskQuery().singleResult();
System.out.println("第一个任务完成前,当前的任务名为：" + taskA.getName());
taskService.complete(taskA.getId());
Task taskB = taskService.createTaskQuery().singleResult();
System.out.println("第二个任务完成前,当前任务名为：" + taskB.getName());
taskService.complete(taskB.getId());
Task taskC = taskService.createTaskQuery().singleResult();
System.out.println("流程结束后,查找任务：" + taskC);
}
}
这是报错
log4j:WARN No appenders could be found for logger (org.activiti.engine.ProcessEngines).
log4j:WARN Please initialize the log4j system properly.
log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.
Exception in thread "main" java.lang.NullPointerException
at org.start.main.Main.main(Main.java:13)
------解决思路----------------------
是不是少了log4j包?或该包有版本冲突。