# Filter Function
This module provides a filter function that can be reused and composed in other applications.
## Beans for injection
You can import the `FilterFunctionConfiguration` in a Spring Boot application and then inject the following bean.
`filterFunction`
You can use `filterFunction` as a qualifier when injecting.
Once injected, you can use the `apply` method of the `Function` to invoke it and get the result.
## Configuration Options
All configuration properties are prefixed with `filter.function`.
For more information on the various options available, please see link:src/main/java/org/springframework/cloud/fn/filter/FilterFunctionProperties.java[FilterFunctionProperties.java]
## Examples
See this link:src/test/java/org/springframework/cloud/fn/filter/FilterFunctionApplicationTests.java[test suite] for examples of how this function is used.
## Other usage
See this link:../../../applications/processor/filter-processor/README.adoc[README] where this function is used to create a Spring Cloud Stream application.