Spring Property Injection Concepts: Difference between revisions

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==Command-Line Arguments==
==Command-Line Arguments==
java -jar ... --<''property.name''>=<''value''>


==Environment Variables==
==Environment Variables==

Revision as of 20:18, 21 November 2018

Internal

Overview

Spring has two different, but related kinds of configurations: bean wiring, which refers to declaring application components and their dependencies, and how those dependencies should be injected into each other, as described in the Dependency Injection and Inversion of Control Container section, and property injection, which is the process that allows external pieces of data, known as configuration properties, to be provided to the application runtime at startup or while it is running, in form of Java system properties, environment variables and by other means. This section addresses property injection concepts.

Configuration Properties

Configuration properties are pieces of data coded into Spring components using the JavaBeans property conventions. They usually have a corresponding member variable, a getter and a setter. The Spring Framework provides conventions and mechanisms to automatically inject values into configuration properties, while those values come from several different property sources.

The Environment Abstraction

The Spring environment is the only source of configuration properties for components needing them. The environment abstracts the origins of properties and applies precedence rules when the same property is specified in more than one source. It pulls property values from several sources: Java system properties, command-line arguments, environment variables, configuration files, etc. The property sources are described in detail in their corresponding sections, below.

Injecting Properties into Beans

Property Injection and Auto-Configuration

The beans that are automatically configured by the Spring Boot autoconfiguration. process are all configurable by properties drawn from the Spring environment.

Property Sources

Java System Properties

Command-Line Arguments

java -jar ... --<property.name>=<value>

Environment Variables

Property Configuration Files

Configuration Service

Precedence

Profiles




application.properties

application.properties

Application Arguments

Environment Variables

Profile

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