Adding Gateway Diagram Elements for BPMs

Updated on 2025-03-24 GMT+08:00

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Gateway diagram elements control the process execution direction, and can be considered as decisions and judgments.

Exclusive Gateway

An exclusive gateway is used to make a unique decision for a group of branches in a process. The system evaluates the branch that flows out of the gateway based on the Condition Order. The process executes the first branch whose connection condition is evaluated as true (when multiple conditions are evaluated as true, the first decision is executed) and does not evaluate the subsequent branches. If all branch condition decisions are false and the gateway defines a default connection, the default branch is executed. If there is no reachable branch, an exception is thrown and the BPM is interrupted. This situation should be avoided in the BPM design.

Figure 1 Exclusive Gateway Detail page

Figure 2 Branch connection configuration

Parallel Gateway

Parallel gateways are used to combine branches unconditionally. Such gateways ignore connection conditions. A BPM can have multiple incoming and one outgoing branches, which are concurrently executed by the BPM engine. The parallel gateway appears in pairs. A pair of gateways can have multiple parallel branches.

Figure 3 Parallel gateway

Inclusive Gateway

An inclusive gateway is a special type of parallel gateway. On the basis of a parallel gateway, a condition can be configured for each connection line. All connection lines that meet the condition are executed concurrently. No. If a default branch is configured, the default branch is executed. Each inclusive gateway should appear in pairs, starting from the inclusive divergent gateway and finally connecting to the aggregation gateway.

Figure 4 Inclusive gateway

Event-Based Gateway

Generally, the gateway determines the subsequent path based on the connection condition, which requires that the condition information exists in the process. However, if the conditions for selecting the subsequent path are not from the process, event-based gateways can be used. The event-based gateway has only the branch behavior. It allows the branch (such as a time event or message event) where the event reaches first to be selected from multiple candidate branches and the other branches to be cancelled.

The connection target after the event-based gateway must be a Signal Catch or Timer Catch event.

Figure 5 Event gateway