網(wǎng)路冷眼@BlogJava

We already spoke about business processes and the BPM life-cycle, but there is a lot of other terminology used in the BPM space. Therefore we will look at the most important parts of the BPM language in this chapter to get up to speed for the rest of this book.

盡管我們已經(jīng)談到業(yè)務(wù)流程和BPM生命周期，但是在BPM空間里還有許多其它的術(shù)語。所以我們將在本章來看看BPM 語言的最重要的部分，以便加快本書后面的速度。

1.2.1 Getting the big picture （獲取大圖）

First, let’s look at the big picture of the BPM terminology by looking at a typical BPM architecture. Such an architecture is implemented by a business process management system or suite if you like (BPMS). There are a lot of software vendors who provide BPMS software (such as IBM, Oracle, Tibco, Intalio and of course Alfresco with Activiti), but all their suites contain similar tools. Figure 1.3 provides an overview of a typical BPM architecture.

首先，通過典型的BPM架構(gòu)，讓我們來認(rèn)識BPM術(shù)語的大圖。通過一個流程管理系統(tǒng)或者套件來實現(xiàn)這個架構(gòu)。有許多軟件商提供BPMS軟件（比如IBM，Oracle，Tibco，Intalio，當(dāng)然開發(fā)Activiti的Alfresco）,但是他們的套件包括相似的工具。圖1.3提供典型架構(gòu)的概況。

Figure 1.3 An overview of a typical BPMS architecture, with a process engine in its core and surrounded by process modeling, monitoring and life-cycle management tools.

圖1.3 典型的BPMS架構(gòu)的概貌，流程引擎是核心，周圍是流程建模、監(jiān)視和生命周期管理工具

There are quite a lot of components mentioned in figure 1.3, but the core of a BPMS is without doubt the process engine. In most chapters of this book we’ll therefore discuss this part of a BPMS in detail. The process engine is responsible for handling the process state for example. Because processes can run for days, weeks or even months it’s vital that the process state is persisted in a database. In case of hardware or software failure, the process

state can always be recovered based on the process state retrieved from the database.

圖1.3中提及相當(dāng)多的組件，但是，毫無爭議，BPMS的核心是流程引擎。本書的大部分章節(jié)，我們將詳細(xì)討論BPMS的這部分內(nèi)容。流程引擎負(fù)責(zé)處理流程狀態(tài)。因為流程引擎能夠運行數(shù)日，數(shù)周，甚至數(shù)月，所以將流程狀態(tài)持久化到數(shù)據(jù)庫是至關(guān)重要的。萬一硬件或者軟件出故障，流程狀態(tài)總能基于數(shù)據(jù)庫檢索的流程狀態(tài)，從而得以恢復(fù)。

In the rest of this section we will look at each of the four core components of a BPMS architecture, first the process engine, then the process modeling tools, third the process monitoring tools and eventually the process life-cycle management tools.

本節(jié)的其余部分，我們將看看BPMS架構(gòu)的一個核心部件。首先是流程引擎，然后是流程建模工具，第三是監(jiān)視工具，最后是流程生命周期管理工具。

1.2.2 Exploring the core process engine （探索核心的流程引擎）

A process engine is the foundation for a business process management suite. The process engine is capable of executing the business process model with quality aspects such as availability, performance and robustness in mind. In the next subsections we discuss the core parts of the process engine, the process state manager and the human task manager. The business rule engine integration will be discussed in chapter 9 and we’ll be talking about

the process history service in chapter 12 and 13.

流程引擎是業(yè)務(wù)流程管理套件的基礎(chǔ)。流程引擎有能力處理可用度、性能和魯棒性的質(zhì)量方面。在子節(jié)我們討論流程引擎的核心部分，流程狀態(tài)管理器和人工任務(wù)管理器。業(yè)務(wù)規(guī)則引擎的集成將在第9章討論。第12章和第13章將討論流程歷史服務(wù)。

PROCESS STATE MANAGEMENT（流程狀態(tài)管理）

One of the common requirements of a business process is that it must be able to run over a longer period such as a day or a week. In that period the business process must be capable of accepting requests and handling events and progress a step further in the business process definition. A simple implementation of a process engine supporting this requirement would keep the running business processes in memory until it eventually reaches its end state. This would however lead to a very high consumption of memory when a lot of business processes are running.

業(yè)務(wù)流程公共需求之一是它必須能長久運行，數(shù)日或者數(shù)周。在此周期，業(yè)務(wù)流程必須有能力接受請求，處理事件和讓業(yè)務(wù)流程定義的步驟進(jìn)一步前行。支持這個需求的流程引擎的簡單實現(xiàn)是在內(nèi)存保持業(yè)務(wù)流程運行，直到最后到達(dá)結(jié)束狀態(tài)。但是，當(dāng)許多業(yè)務(wù)流程運行時，這將導(dǎo)致很高的內(nèi)存消耗。

Therefore a core capability of a process engine is to have good process state management. A common solution for managing the process state is to have the current state of a process stored in a database at certain points in a process execution. When we talk about the process state you can think of the following parts of a process:

所以，業(yè)務(wù)流程的核心能力是具有良好的流程狀態(tài)管理。管理流程狀態(tài)的公共的解決方案是在流程執(zhí)行中的某個時間點讓當(dāng)前狀態(tài)存儲在數(shù)據(jù)庫里。當(dāng)面談及流程狀態(tài)時，你能考慮下列流程部分：

•     Process variables
•     流程變量
•     The current activity in the process execution, often named the process execution token.
•      流程執(zhí)行的當(dāng)前活動，通常稱為流程令牌。
•     Assigned users / groups in a user task
•      用戶任務(wù)里分配的用戶/組
•    The start and end time of executed process activities
•     執(zhí)行流程活動的開始和結(jié)束時間。

Because the process state is stored in a database, the process engine can also recover running processes after a server shutdown, due to hardware failure or regular maintenance. So the process state manager is a vital component of the process engine.

因為流程狀態(tài)存儲在數(shù)據(jù)庫，所以流程引擎在服務(wù)器關(guān)閉之后可以恢復(fù)運行流程。服務(wù)的關(guān)閉是由于硬件故障或者正常維護(hù)。所以流程狀態(tài)管理器是流程引擎的至關(guān)重要的組件。

HUMAN TASK MANAGER（人工任務(wù)管理）

Another important component of a process engine is a human task manager to support workflow functionality. With workflow functionality, we mean the creation of user or group assigned tasks during process execution. In BPMN 2.0 this can be implemented with the user task construct.

人工任務(wù)管理器是另外一個重要的流程引擎的組件。它支持工作流功能。在工作流功能的幫助下，能在流程執(zhí)行當(dāng)中建立分配任務(wù)的用戶和組。在BPMN 2.0，可以用用戶，用戶組組件來實現(xiàn)。

The human task manager should be capable of assigning tasks to specific users or groups of users. This also means that an API must be available to query the human task manager for tasks available to a specific user. A task can have at least three different states.

人工任務(wù)管理器應(yīng)該具有將任務(wù)分配給某些用戶或組的能力。這也意味著，為了查詢某一用戶可用的任務(wù)，必須有可用的API來查詢?nèi)蝿?wù)管理器，任務(wù)至少具有三個不同的狀態(tài)。

1. The task is unassigned, which means that the task is available to every user that is part of the user or group criteria specified in the task configuration.

1.任務(wù)分配，這意味著對每個用戶可用的任務(wù)是在任務(wù)配置中指定的用戶或組基準(zhǔn)的一部分。

2. The task is assigned, which means the task is assigned to one and only one user. This user has claimed the task, so the task will not appear on other user’s task lists. Of course administrators and managers still can perform commands on this tasks in exceptional cases.

2. 任務(wù)已分配，這意味著一個任務(wù)當(dāng)且僅當(dāng)分配給一個用戶。因為這個用戶已領(lǐng)取任務(wù)，所以這個任務(wù)不會出現(xiàn)在另外用戶的任務(wù)列表當(dāng)中。當(dāng)然在異常情況下，管理員和經(jīng)理用戶仍然能執(zhí)行這個任務(wù)的指令。

3. The task is completed, which means the task is completed by the user who has claimed the task in the first place.

3.任務(wù)完成。由在第一步領(lǐng)取任務(wù)的用戶完成這個任務(wù)

User or group criteria define the users who can claim a user task. Often, there is support

for LDAP queries to fill-in this criteria.

用戶或組基準(zhǔn)定義領(lǐng)取任務(wù)的用戶。經(jīng)常地，采用LDAP查詢支持來滿足這個基準(zhǔn)。

1.2.3 Modeling and design tools （建模和設(shè)計工具）

It’s great to have a process engine to run your business processes, but a BPMS also need modeling and design tools to create the business processes. Before BPMN 2.0 it was easier to differentiate between modeling and design tools, because modeling tools used a modeling notation like BPMN 1.x and design tools used a process execution language like WS-BPEL or jPDL for jBPM.

盡管擁有流程引擎來運行你的業(yè)務(wù)流程，但是BPMS也需要建模和設(shè)計工具來建立業(yè)務(wù)流程。在BPMN 2.0之前，區(qū)分建模工具和設(shè)計工具是比較容易的，這是因為建模工具使用像BPMN 1.想的建模符號，設(shè)計工具使用WS-BPEL或者就BPM的jPDL的流程執(zhí)行語言。

With BPMN 2.0 we now have a standard that provides a modeling notation as well as a process execution language. This means that it’s not necessary any more to convert and transform a BPMN 1.x business process model to WS-BPEL. But as we will see in section 1.3.3, there’s still a difference between the level of detail used in modeling and design phases. A modeling tool has to support features to do high-level modeling and a design tool must be able to create a process execution model that can be directly deployed to a process engine. There may be tools which support modeling as well as design functionality, but we’ll discuss the functionality separately here.

BPMN 2.0既提供了建模符號的標(biāo)志，也提供了流程執(zhí)行語言的標(biāo)準(zhǔn)。這意味著，將BPMN 1.x業(yè)務(wù)建模語言轉(zhuǎn)為WS-BPEL不再有必要。但是，正如我們將在1.3.3所見，建模和設(shè)計階段所使用的細(xì)節(jié)層次仍有差別。建模工具不得不支持高層次的建模特性；而設(shè)計工具必須能建立能夠直接部署到流程引擎的的流程執(zhí)行模型。盡管也許存在既支持建模，也支持設(shè)計功能的工具，但是，我們在此分開討論這些功能。

MODELING A BPMN BUSINESS PROCESS（對BPMN業(yè)務(wù)流程建模）

A BPMN modeling tool should support the definition of business processes by business and information analysts. This means that in a modeling tool we don’t want to be restricted too much by the formal BPMN 2.0 specification, but the focus should be to support the user in the definition of the business process model in a user-friendly way.

BPMN建模工具應(yīng)該支持業(yè)務(wù)和信息分析師定義的業(yè)務(wù)流程。盡管這意味著我們不想被正式的BPMN 2.0規(guī)范限制太多，但是應(yīng)該關(guān)注以用戶友好的方式支持用戶業(yè)務(wù)流程模型的定義。

In addition, it would be nice to see simulation functionality in the modeler to be able to see if the modeled business process executes as expected. There are pretty advanced simulation tools available that can calculate maximum throughput and can identify possible bottlenecks in a business process and this is vital functionality to do successful BPM.

另外，在建模器里最好提供仿真功能，以便能夠觀察建模的業(yè)務(wù)流程是否以期望的方式運行。具有可用的非常棒的高級仿真工具能夠計算最大的吞吐量和辨識業(yè)務(wù)可能的瓶頸。這是成功BPM至關(guān)重要的功能。

DESIGNING A BPMN BUSINESS PROCESS （對BPMN業(yè)務(wù)流程進(jìn)行）

The designer tool takes a BPMN business process defined in the modeler as starting point or you can decide to design a business process from scratch if you want to. A designer tool is often dedicated to support a specific implementation of a process engine. Where a modeler tool can and should be vendor independent, a designer can contain vendor specific details and have support for vendor specific functionality inside a process engine.

設(shè)計器工具是從建模器取得定義BPMN業(yè)務(wù)流程作為起始點。如果你希望從頭開始，你能夠決定設(shè)計一個從頭開始的業(yè)務(wù)流程。設(shè)計工具經(jīng)常是專有的支持，流程引擎特有的實現(xiàn)。建模器工具能夠并應(yīng)該是供應(yīng)商獨立的，而設(shè)計器可以包括供應(yīng)商相關(guān)的細(xì)節(jié)，并可在流程引擎里具有對特定功能的支持。

Important functionality for a designer is to be able to add for example error handling to a process, to couple service tasks to web services via WSDL and Java classes, and to couple user tasks to LDAP related queries. Furthermore, it must be possible to run a process engine from within the designer tool and deploy processes on it for testing purposes. Finally it must support unit testing, so a developer is able to perform some basic unit tests before a process is deployed to a central process engine.

1.2.4 Managing and monitoring the process engine （管理和監(jiān)視流程引擎）

Management functionality for a process engine means that an administrator must be able to query the process engine for deployed process definitions and look into version information. In addition, running process instances can be queried to look into specific states of processes when end users have questions about it. Also for user tasks it must be possible to claim and complete certain user tasks when there is a need for this.

流程引擎的管理功能意味著管理員必須能夠查詢已部署的流程定義和檢查版本信息。另外，當(dāng)用戶有問題時，能夠查詢正運行的流程引擎來深入分析流程狀態(tài)，對于用戶任務(wù)，當(dāng)必須時，必須有可能領(lǐng)取和完成某些用戶任務(wù)。

In general, the state of a process definition, process instance and user task must be available for an administrator. This also includes the process engine databases, which are a core part of the process engine. So the database model and its tables should be easily accessible for administration purposes.

通常，流程定義，流程實例以及用戶任務(wù)的狀態(tài)對管理員可用。這也包括流程引擎數(shù)據(jù)庫，它是流程引擎的核心部分。所以為了管理目的，應(yīng)該訪問數(shù)據(jù)庫模型和它的數(shù)據(jù)庫表。

Monitoring functionality is more targeted at specific events that occur in a process instance. For example, when a large order enters an order process, it may be interesting for specific managers to receive a signal. Another more technical example is that a process instance is inactive for more than a week, it may need attention to see if the process is still running normally. It’s obvious that management and monitoring is a very important part in the business success of process engines and BPM in general.

監(jiān)視器功能更多關(guān)注在流程實例發(fā)生的特殊事件。例如，當(dāng)以大宗訂單進(jìn)入一個訂單流程。某個經(jīng)理將受到信號是否有趣。另外一個更技術(shù)是一個流實現(xiàn)超過一周不激活。也許引起注意看看流程是否仍然運行。顯然，通常業(yè)務(wù)成功和BPM管理和監(jiān)視是非常重要的。

1.2.5 Collaborating on business processes （業(yè)務(wù)流程協(xié)作）

Collaboration tools are a central part of a lot of IT projects in general. Collaboration tools include for example source code repositories, code review tools and wiki pages. But in BPM projects it’s even more important due to the complexity and the large amount of different roles and persons in such a project.

通常，協(xié)作工具是許多IT項目的中央部分。例如，協(xié)作工具包括源代碼倉庫，代碼走查工具和wike頁面。由于項目的復(fù)雜性，大規(guī)模的角色和人，BPM項目甚至更為重要。

BPMN provides a good foundation for collaboration because it supports high level business modeling understood by managers, it also supports detailed business modeling understood by business analysts, architects and designers and with BPMN 2.0 it also support process execution understood by architects, developers and administrators.

BPMN為協(xié)作提供了良好基礎(chǔ)。這是因為，它為經(jīng)理提供易理解的高層次業(yè)務(wù)建模能力；也為業(yè)務(wù)分析師，架構(gòu)師提供了易理解、更為詳細(xì)的業(yè)務(wù)建模。采用BPMN 2.0架構(gòu)師，開發(fā)人員和管理人員提供易理解的流程執(zhí)行。

A BPM collaboration tool must provide a view on the different process model repositories of a BPM project. There are modeler, designer and even code repositories which must be bundled in one or more views depending on the end user. It’s also very important that everybody working on a business process is identifiable with his role and work in this collaboration tool. It must be clear which person must be contacted for specific questions.

BPM協(xié)作工具必須提供BPM項目不同流程模型倉庫的視圖。根據(jù)用戶不同，必須能夠綁定建模器、設(shè)計器，甚至代碼倉庫包圖。在這個協(xié)作工具里，根據(jù)角色和工作辨識在業(yè)務(wù)流程上工作的每個人也非常重要。某個問題聯(lián)系人必須非常清楚。

We rushed through the major components of the typical BPM architecture we showed in figure 1.3. But we’ll take a closer look at every part in the rest of this book. For example we’ll look at the process engine in chapter 3, discuss the human task manager in chapter 7 and look at the modeler, designer and collaboration tools in chapter 2. For now it’s good to have heard about the vocabulary, as we will be using it a lot in this book.

我們快速瀏覽了圖1.3所示的典型BPM架構(gòu)的主要部件。但是，我們將在本書的其余部分仔細(xì)觀察每個部件。例如，在第3章，我們將介紹流程引擎。在第7章，討論人工任務(wù)管理器。在第2章討論建模器、設(shè)計器和協(xié)作工具。到目前為止，我們已經(jīng)擁有了共同的詞匯，這很棒，因為我們將在本書使用這些詞匯。

With a foundation of BPM knowledge and vocabulary in our minds it’s time to get introduced into BPMN 2.0 and its history.

既然我們已經(jīng)對BPM只是和詞匯了然于心，是該介紹BPMN 2.0及其歷史的時間了。