Web3j implements AutoClosable Interface (LFDT-web3j#2102)

Signed-off-by: Steffen Börner <[email protected]>
Signed-off-by: Shashank Kumar <[email protected]>

Author: steffenboe

core/src/main/java/org/web3j/protocol/Web3j.java

@@ -21,7 +21,7 @@
 import org.web3j.protocol.rx.Web3jRx;
 
 /** JSON-RPC Request object building factory. */
-public interface Web3j extends Ethereum, Web3jRx, Batcher, BlobFee {
+public interface Web3j extends Ethereum, Web3jRx, Batcher, BlobFee, AutoCloseable {
 
     /**
      * Construct a new Web3j instance.

core/src/main/java/org/web3j/protocol/core/JsonRpc2_0Web3j.java

@@ -906,4 +906,9 @@ private static BigInteger fakeExponential(BigInteger numerator) {
         }
         return output.divide(BLOB_BASE_FEE_UPDATE_FRACTION);
     }
+
+    @Override
+    public void close() throws Exception {
+        this.shutdown();
+    }
 }

core/src/test/java/org/web3j/protocol/core/JsonRpc2_0Web3jTest.java

@@ -37,8 +37,7 @@ public class JsonRpc2_0Web3jTest {
     public void testStopExecutorOnShutdown() throws Exception {
         web3j.shutdown();
 
-        verify(scheduledExecutorService).shutdown();
-        verify(service).close();
+        verifyServicesClosed();
     }
 
     @Test
@@ -52,4 +51,15 @@ public void testExceptionOnServiceClosure() throws Exception {
                     web3j.shutdown();
                 });
     }
+
+    @Test
+    public void shouldShutdownOnAutoClose() throws Exception {
+        try (Web3j web3j = Web3j.build(service, 10, scheduledExecutorService)) {}
+        verifyServicesClosed();
+    }
+
+    private void verifyServicesClosed() throws IOException {
+        verify(scheduledExecutorService).shutdown();
+        verify(service).close();
+    }
 }