Stream Explorer and JMS for both inbound and outbound interaction

In this article, we will look at the very common interaction between Stream Explorer and JMS. JMS is a commonly used channel for decoupled exchange of messages or events. Stream Explorer can both consume messages from a JMS destination (through Stream) and publish findings to a JMS destination (with a target). The use case we discuss here is about temperature sensors: small devices distributed over a building, measuring the local room temperature every few seconds (more...)

Interacting with JMS Queue and Topic from Java SE

This article is just a quick post of some code I want to have easy access to. It runs in Java SE – outside any container in a stand alone JVM. It creates a connection with a JMS Queue. One class sends messages to the Queue, the other class registers as a listener and consumes messages from a different queue.

I have created the code in JDeveloper. It runs stand-alone and connects to a WebLogic (more...)

AMIS organiseert: Workshop Stream Explorer and Oracle Event Processor – Dinsdag 19 mei 2015, 17.30 uur

imageDinsdag 19 mei vanaf 17.30 uur vindt bij AMIS (Edisonbaan 15, Nieuwegein) een gratis community workshop plaats over Stream Explorer en Oracle Event Processor in het kader van de AMIS SOA SIG. Lucas Jellema zal een presentatie geven waarin hij Stream Explorer introduceert. Hij laat een aantal demonstraties zien van Stream Explorer, OEP en de interactie met SOA Suite 12c. Vervolgens krijgens deelnemers de beschikking over een Virtual Machine (Stream Explorer, OEP, SOA Suite (more...)

StreamExplorer pushing findings as JSON messages to a WebSocket channel for live HTML Dashboard updates

A common desire when doing real time event processing with Stream Explorer and/or Oracle EVent Processor is the ability to present the findings from Stream Explorer in a live dashboard. This dashboard should hold a visualization of whatever information we have set up Stream Explorer to find for us – and it should always show the latest information.

User interfaces are commonly presented in web browsers and created using HTML(5) and JavaScript. As part of (more...)

Java Web Application sending JSON messages through WebSocket to HTML5 browser application for real time push

imageThis article describes a Java EE 7 web application that exposes a REST service that handles HTTP POST requests with JSON payload. Any message received is sent through a Web Socket to the web socket (server) endpoint that is published by a Java Class deployed as part of the web application. A static HTML page with two associated JavaScript libraries is opened in a web browser and has opened a web socket connection to this (more...)

Publish a REST service from PL/SQL to handle HTTP POST requests – using the embedded PL/SQL gateway

Oracle Database can act as an HTTP server – using the Embedded PL/SQL Gateway (the 10g successor of the MOD_PLSQL gateway). With just a few statements, we can have the Oracle Database become a listener to HTTP requests (GET or POST). When requests are received at the configured host, port and URL, the request is passed to a PL/SQL procedure that handles it and prepares a response.

In this article, we will expose a REST (more...)

StreamExplorer – use REST adapter to feed results from event processing to a REST service

In a recent article, I described how StreamExplorer can be configured to consume events by exposing a REST service to which clients can send HTTP POST requests with JSON payloads. StreamExplorer also can make use of an Outbound REST Adapter through which results of explorations can be sent.

This target service can be implemented in a number of ways – that does not concern StreamExplorer. In this case we will use an implementation in (more...)

Use the inbound REST adapter of StreamExplorer to consume events from HTTP POST requests

StreamExplorer is a fairly recent product from Oracle – a business user friendly layer around Oracle Event Processor. In various previous articles, I have discussed StreamExplorer. I have demonstrated how SX can consume events from JMS, EDN and from CSV files. This article shows how a stream in StreamExplorer can expose a REST service to which events can be pushed.

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In this case, we will look at a movie theater. More specifically, we will monitor (more...)

Make HTTP POST request from Java SE – no frills, no libraries, just plain Java

This article shows a very simple, straightforward example of making an HTTP POST call to a url (http://localhost:8080/movieevents) and sending a JSON payload to that URL. This example does not use any additional libraries – just the standard Java SE libraries.

package nl.amis.rest;

import java.io.BufferedReader;
import java.io.DataOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;

import java.io.Reader;

import java.io.UnsupportedEncodingException;

import java.net.HttpURLConnection;
import java. (more...)

Invoke a REST service from PL/SQL – make an HTTP POST request using UTL_HTTP in Oracle Database 11g XE

This article is small and simple. It discusses how from PL/SQL an HTTP POST request can be made to a REST service. This particular service is exposed at http://localhost:9002/cinema and it expects a POST call.

Making HTTP requests from PL/SQL is fairly simple, using the supplied package UTL_HTTP. Starting in Oracle Database 11g, some security constraints are in force around network interactions. This means that before from a specific database account a PL/SQL unit can (more...)