snaker-core/src/main/java/org/snaker/engine/core/SnakerEngineImpl.java
public Order startInstanceById(String id, String operator, Map<String, Object> args) {
		if(args == null) args = new HashMap<String, Object>();
		Process process = process().getProcessById(id);
		process().check(process, id);
		return startProcess(process, operator, args);
	}
public Order startInstanceById(String id, String operator, Map<String, Object> args) {
		if(args == null) args = new HashMap<String, Object>();
		Process process = process().getProcessById(id);
		process().check(process, id);
		return startProcess(process, operator, args);
	}
根据流程定义ID，操作人ID，参数列表启动流程实例