ensure java 6 compatable

.github/workflows/pipeline.yml

@@ -10,6 +10,34 @@ on:
     branches: [ master ]
 
 jobs:
+  # old-school build and jar method. No tests run or compiled.
+  build-1_6: 
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        # build for java 1.6, however don't run any tests
+        java: [ 1.6 ]
+    name: Java ${{ matrix.java }}
+    steps:
+      - uses: actions/checkout@v3
+      - name: Setup java
+        uses: actions/setup-java@v1
+        with:
+          java-version: ${{ matrix.java }}
+      - name: Compile Java ${{ matrix.java }}
+        run: |
+          mkdir -p target/classes
+          javac -version
+          javac -d target/classes/ src/main/java/org/json/*.java
+      - name: Create java ${{ matrix.java }} JAR
+        run: |
+          jar cvf target/org.json.jar -C target/classes .
+      - name: Upload JAR ${{ matrix.java }}
+        if: ${{ always() }}
+        uses: actions/upload-artifact@v3
+        with:
+          name: Create java ${{ matrix.java }} JAR
+          path: target/*.jar
   build:
     runs-on: ubuntu-latest
     strategy: