Class EnvarBasedValueSource

  • All Implemented Interfaces:
    ValueSource

    public class EnvarBasedValueSource
    extends AbstractValueSource
    ValueSource which resolves expressions against the environment variables available from the underlying operating system (and possibly, the shell environment that created the present Java process). If the expression starts with 'env.', this prefix is trimmed before resolving the rest as an environment variable name.
    • Constructor Summary

      Constructors 
      Constructor Description
      EnvarBasedValueSource()
      Create a new value source for interpolation based on shell environment variables.
      EnvarBasedValueSource​(boolean caseSensitive)
      Create a new value source for interpolation based on shell environment variables.
    • Field Detail

      • envarsCaseSensitive

        private static java.util.Properties envarsCaseSensitive
      • envarsCaseInsensitive

        private static java.util.Properties envarsCaseInsensitive
      • envars

        private final java.util.Properties envars
      • caseSensitive

        private final boolean caseSensitive
    • Constructor Detail

      • EnvarBasedValueSource

        public EnvarBasedValueSource()
                              throws java.io.IOException
        Create a new value source for interpolation based on shell environment variables. In this case, envar keys ARE CASE SENSITIVE.
        Throws:
        java.io.IOException - in case of an error.
      • EnvarBasedValueSource

        public EnvarBasedValueSource​(boolean caseSensitive)
                              throws java.io.IOException
        Create a new value source for interpolation based on shell environment variables.
        Parameters:
        caseSensitive - Whether the environment variable key should be treated in a case-sensitive manner for lookups
        Throws:
        java.io.IOException - in case of an error.
    • Method Detail

      • getEnvars

        private static java.util.Properties getEnvars​(boolean caseSensitive)
                                               throws java.io.IOException
        Throws:
        java.io.IOException
      • getValue

        public java.lang.Object getValue​(java.lang.String expression)
        If the expression starts with 'env.' then trim this prefix. Next, resolve the (possibly trimmed) expression as an environment variable name against the collection of environment variables that were read from the operating system when this ValueSource instance was created.
        Parameters:
        expression - envar expression, like 'HOME' or 'env.HOME'
        Returns:
        the environment variable value for the given expression
      • resetStatics

        static void resetStatics()
        reset static variables acting as a cache for testing purposes only