private void freeNative() {
        lock.writeLock().lock();
        try {
            if (isValid()) {
                long toFree = sslCtxNativePointer;
                sslCtxNativePointer = 0;
                NativeCrypto.SSL_CTX_free(toFree, this);
            }
        } finally {
            lock.writeLock().unlock();
        }
    }
Returns a native pointer to a new SSL object in this SSL_CTX.
common/src/main/java/org/conscrypt/AbstractSessionContext.java