TL;DR Summary Java Type DB Type Description SAVE Long NUMBER Just using a long as milliseconds, between the current time and midnight, January 1, 1970 UTC is the most secure way. SAVE Instant NUMBER Using in Java an Instant and converting it into a NUMBER to save it in the DB will also avoid any…
Overview To enable Activiti in our JEE project the following steps are needed: Add the maven dependencies — include spring-context Add log4j configuration Add the activiti configuration for CDI integration activiti.cfg.xml Add your first activiti workflow Add an activiti compatible data source to your container Deploy and run it Git Project. Eclipse Plugin To install the…
The problem Sometimes we want to register a default Entity Listeners which are called as soon an entity is persisted, without adding the @EntityListeners annotation to our classes, as in most cases we anyway provide interfaces so we can access data on the entity itself. The problem is, that we cannot annotate our entity listener with…
Create vs. Get AngularJS application The module dependency array tells AngularJS to create an app, otherwise to load it: Create myApp var app = angular.module(‚myApp‘, []); Get myApp var app = angular.module(‚myApp‘); Binding @ Text binding, expressions are supported using {{ }} = Two-way binding & Method binding < One-way binding (usually for components) ?…
Problem Sometimes it is confusing how fragments work in Android and interesting side effects like: Why have Fragments empty constructors? Why shouldn’t I pass state variables like they are? Why do I need this Fragment transactions? What does addToBackStack mean and do I need it? Why is sometimes the Activity null in my fragment? Overview…
Problem Often we want to connect to create a secure SSL connection to an HTTPs endpoint which is secured by a self-signed Certificate. If we do so just with a simple call we usually face an nice exception like: Caused by: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested…
The Problem Sometimes we want to bind an Android Service in our activities and wrap inside e.g. our communication to our backend. Now the problem arises when we unbind it again. As usually if we change activities we want this service to survive and be in the very next activity. As soon as we close…
Problem Often we want an easy way to test our REST services. Even if where are many tools around e.g. Chrome Plugins etc. it is maybe easier on servers to juts use curl to do the job. Basic PUT command curl -X PUT -H „<Header-Name>: <Header-Value>“ „https://<url>“ -v Add basic Authorization Curl already supports basic auth…
The Problem Recently using MongoDB and Spring Data I encountered an interesting issue. Saving an Entity which was loaded by @DBRef(lazy = true) wasn’t possible together with the activated ValidatingMongoEventListener. Each time the following error occurred: javax.validation.ConstraintViolationException at org.springframework.data.mongodb.core.mapping.event.ValidatingMongoEventListener.onBeforeSave(ValidatingMongoEventListener.java:65) at org.springframework.data.mongodb.core.mapping.event.AbstractMongoEventListener.onBeforeSave(AbstractMongoEventListener.java:144) at org.springframework.data.mongodb.core.mapping.event.AbstractMongoEventListener.onApplicationEvent(AbstractMongoEventListener.java:90) at org.springframework.data.mongodb.core.mapping.event.AbstractMongoEventListener.onApplicationEvent(AbstractMongoEventListener.java:33) at org.springframework.context.event.SimpleApplicationEventMulticaster.invokeListener(SimpleApplicationEventMulticaster.java:163) at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:136) at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:381) at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:335) at org.springframework.data.mongodb.core.MongoTemplate.maybeEmitEvent(MongoTemplate.java:1633) at org.springframework.data.mongodb.core.MongoTemplate.doSave(MongoTemplate.java:986) at org.springframework.data.mongodb.core.MongoTemplate.save(MongoTemplate.java:933)…
Problem Sometimes we the Keyboard doesn’t show up by default if we e.g. open a dialog and request the focus for an input element. Even following the default tutorials doesn’t really help. As soo here some samples how it will show up. Solution Show Keyboard in Dialogs / DialogFragment Usually the solution the the Android…