Connection created by SingleConnectionDataSource with suppressClose=true always returns isClosed=false even if the target connection is closed #24853
Description
If SingleConnectionDataSource is configured with suppressClose=true it will produce a Connection wrapped in CloseSuppressingInvocationHandler. CloseSuppressingInvocationHandler will always return false if the isClosed() is being triggered on the wrapped connection. This is ok until SingleConnectionDataSource#destroy() is triggered which closed the connection on the wrapped Connection.
I'd therefore suggest to change
/** * Invocation handler that suppresses close calls on JDBC Connections. */ private static class CloseSuppressingInvocationHandler implements InvocationHandler { private final Connection target; public CloseSuppressingInvocationHandler(Connection target) { this.target = target; } @Override @Nullable public Object invoke(Object proxy, Method method, Object[] args) throws Throwable { // Invocation on ConnectionProxy interface coming in... if (method.getName().equals("equals")) { // Only consider equal when proxies are identical. return (proxy == args[0]); } else if (method.getName().equals("hashCode")) { // Use hashCode of Connection proxy. return System.identityHashCode(proxy); } else if (method.getName().equals("unwrap")) { if (((Class<?>) args[0]).isInstance(proxy)) { return proxy; } } else if (method.getName().equals("isWrapperFor")) { if (((Class<?>) args[0]).isInstance(proxy)) { return true; } } else if (method.getName().equals("close")) { // Handle close method: don't pass the call on. return null; } else if (method.getName().equals("isClosed")) { return false; } else if (method.getName().equals("getTargetConnection")) { // Handle getTargetConnection method: return underlying Connection. return this.target; } // Invoke method on target Connection. try { return method.invoke(this.target, args); } catch (InvocationTargetException ex) { throw ex.getTargetException(); } } } to
/** * Invocation handler that suppresses close calls on JDBC Connections. */ private static class CloseSuppressingInvocationHandler implements InvocationHandler { private final Connection target; public CloseSuppressingInvocationHandler(Connection target) { this.target = target; } @Override @Nullable public Object invoke(Object proxy, Method method, Object[] args) throws Throwable { // Invocation on ConnectionProxy interface coming in... if (method.getName().equals("equals")) { // Only consider equal when proxies are identical. return (proxy == args[0]); } else if (method.getName().equals("hashCode")) { // Use hashCode of Connection proxy. return System.identityHashCode(proxy); } else if (method.getName().equals("unwrap")) { if (((Class<?>) args[0]).isInstance(proxy)) { return proxy; } } else if (method.getName().equals("isWrapperFor")) { if (((Class<?>) args[0]).isInstance(proxy)) { return true; } } else if (method.getName().equals("close")) { // Handle close method: don't pass the call on. return null; } // else if (method.getName().equals("isClosed")) { // return false; // } else if (method.getName().equals("getTargetConnection")) { // Handle getTargetConnection method: return underlying Connection. return this.target; } // Invoke method on target Connection. try { return method.invoke(this.target, args); } catch (InvocationTargetException ex) { throw ex.getTargetException(); } } } Let me know if this change would be ok then I can create a pull request