Creating ESQL modules

Use the IBM Integration API when developing message flow applications to create ESQL modules. You can then associate ESQL modules with nodes that use ESQL. For example, if you create a Compute node, you can write Java™ code to create an ESQL module and then associate that module with the node.

Examples of nodes that use ESQL are Compute, Database, DatabaseInput, and Filter nodes. If you are using a non-default broker schema, you must set the schema by using the setBrokerSchema() method.

The following example shows you how to create an ESQL module in the mqsi schema. The module is then assigned to a new Compute node by using the setComputeExpression() method:

File msgFlow = new File("main.msgflow");
MessageFlow mf1 = FlowRendererMSGFLOW.read(msgFlow);
ESQLModule module = new ESQLModule();
module.setBrokerSchema("mqsi");
module.setEsqlMain("MyESQLMain");
ComputeNode compNode = new ComputeNode();
compNode.setNodeName("My Compute Node");
compNode.setComputeExpression(module);
mf1.addNode(compNode);

The following example shows you how to create an ESQL module in the default schema. The setBrokerSchema() method is not required.

File msgFlow = new File("main.msgflow");
MessageFlow mf1 = FlowRendererMSGFLOW.read(msgFlow);
File esql = new File("FileBatchProcessingSample_Branch.esql");
ESQLFile esqlFile = new ESQLFile(esql);
Vector<ESQLModule> esqlModules = esqlFile.getEsqlModules();
ComputeNode compNode = new ComputeNode();
compNode.setNodeName("My Compute Node");
compNode.setComputeExpression(esqlModules.get(0));
mf1.addNode(compNode);

The following example shows you how to discover an ESQL module from within an ESQL file by using the getEsqlModules() method. You can then use the ESQL module to set the compute expression on a Compute node by using the setComputeExpression() method.

File msgFlow = new File("main.msgflow");
MessageFlow mf1 = FlowRendererMSGFLOW.read(msgFlow);
File esql = new File("FileBatchProcessingSample_Branch.esql");
ESQLFile esqlFile = new ESQLFile(esql);
Vector<ESQLModule> esqlModules = esqlFile.getEsqlModules();
ComputeNode compNode = new ComputeNode();
compNode.setNodeName("My Compute Node");
compNode.setComputeExpression(esqlModules.get(0));
mf1.addNode(compNode);

Pattern authoring

The following examples are the same as the three previous examples, but tailored for pattern authoring:

MessageFlow mf1 = patternInstanceManager.getMessageFlow("MyFlowProject", "main.msgflow");
ESQLModule module = new ESQLModule();
module.setBrokerSchema("mqsi");
module.setEsqlMain("MyESQLMain");
ComputeNode compNode = new ComputeNode();
compNode.setNodeName("My Compute Node");
compNode.setComputeExpression(module);
mf1.addNode(compNode);

MessageFlow mf1 = patternInstanceManager.getMessageFlow("MyFlowProject", "main.msgflow");
ESQLModule module = new ESQLModule();
module.setEsqlMain("MyESQLMain");
ComputeNode compNode = new ComputeNode();
compNode.setNodeName("My Compute Node");
compNode.setComputeExpression(module);
mf1.addNode(compNode);

MessageFlow mf1 = patternInstanceManager.getMessageFlow("MyFlowProject", "main.msgflow");
File esql = new File("FileBatchProcessingSample_Branch.esql");
ESQLFile esqlFile = new ESQLFile(esql);
Vector<ESQLModule> esqlModules = esqlFile.getEsqlModules();
ComputeNode compNode = new ComputeNode();
compNode.setNodeName("My Compute Node");
compNode.setComputeExpression(esqlModules.get(0));
mf1.addNode(compNode);