ci: test with Java 21

Author: yeikel

.github/workflows/pipeline.yml

@@ -15,7 +15,7 @@ jobs:
     strategy:
       matrix:
         # build against supported Java LTS versions:
-        java: [ 8, 11, 17 ]
+        java: [ 8, 11, 17, 21 ]
     name: Java ${{ matrix.java }}
     steps:
       - uses: actions/checkout@v3

README.md

@@ -24,7 +24,7 @@ Project goals include:
 * No external dependencies
 * Fast execution and low memory footprint
 * Maintain backward compatibility
-* Designed and tested to use on Java versions 1.6 - 1.11
+* Designed and tested to use on Java versions 1.8 - 21
 
 The files in this package implement JSON encoders and decoders. The package can also convert between JSON and XML, HTTP headers, Cookies, and CDL.