Package org.apache.tapestry5.ioc.internal.services

## Class SystemEnvSymbolProvider

- java.lang.Object
- - org.apache.tapestry5.ioc.internal.services.SystemEnvSymbolProvider

- All Implemented Interfaces:
    `SymbolProvider`

      public class SystemEnvSymbolProvider
      extends Object
      implements SymbolProvider

  Provides case insensitive access to environment variables. Environment variable symbols are prefixed with "env.".
  Since:
    5.3

- - ### Constructor Summary

    Constructors
    Constructor | Description
    --- | ---
    `SystemEnvSymbolProvider()` |

  - ### Method Summary

    All Methods Instance Methods Concrete Methods
    Modifier and Type | Method | Description
    --- | --- | ---
    `String` | `valueForSymbol​(String symbolName)` | Returns the value for the symbol, or null if this provider can not provide a value.

    - ### Methods inherited from class java.lang.Object

      `clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

- - ### Constructor Detail

    - #### SystemEnvSymbolProvider

          public SystemEnvSymbolProvider()

  - ### Method Detail

    - #### valueForSymbol

          public String valueForSymbol​(String symbolName)

      Description copied from interface: `SymbolProvider`
      Returns the value for the symbol, or null if this provider can not provide a value. The value itself may contain symbols that will be recursively expanded.
      Specified by:
        `valueForSymbol` in interface `SymbolProvider`
      Returns:
        the value or null