# Package org.apache.commons.text.lookup

package org.apache.commons.text.lookup

Provides algorithms for looking up strings for use with a `StringSubstitutor`. The main class in this package is `StringLookupFactory`.

Use `StringLookupFactory` to create instances of string lookups or access singleton string lookups. The main interface is `StringLookup` which is implemented here in package private classes.

Like `BiFunction` is a variant of `Function`, this `BiStringLookup` is a variant of `StringLookup`.

The initial implementation was adapted from Apache Commons Log4j 2.11.0.

Since:
  1.3

- Related Packages
  Package
  Description
  org.apache.commons.text
  Basic classes for text handling.
- Class
  Description
  BiStringLookup<U>
  Lookups a String key for a String value.
  DefaultStringLookup
  An enumeration defining `StringLookup` objects available through `StringLookupFactory`.
  StringLookup
  Lookups a String key for a String value.
  StringLookupFactory
  Create instances of string lookups or access singleton string lookups implemented in this package.