Java Code Examples for io.vavr.control.Try#failure()

public static <E,T> Reader<E,T> addLocationOnError(Reader<E,T> inner, Locator<E> locator) {
    return new Reader<E,T>() {
        @Override
        public Try<T> reset() {
            return inner.reset();
        }

        @Override
        public Try<T> apply(E event) {
            return addLocation(inner.apply(event), locator.getLocation(event));
        }
        
        private Try<T> addLocation(Try<T> t, String location) {
            if (t.isFailure() && t.failed().get() instanceof IllegalArgumentException) {
                return Try.failure(new IllegalArgumentException(t.failed().get().getMessage() + " at " + location, t.failed().get()));
            } else {
                return t;
            }
        }
    };
}
 

/**
 * Returns a supplier which is decorated by a CircuitBreaker.
 *
 * @param circuitBreaker the CircuitBreaker
 * @param supplier       the original function
 * @param <T>            the type of results supplied by this supplier
 * @return a retryable function
 */
static <T> Supplier<Try<T>> decorateTrySupplier(CircuitBreaker circuitBreaker,
    Supplier<Try<T>> supplier) {
    return () -> {
        if (circuitBreaker.tryAcquirePermission()) {
            long start = System.nanoTime();
            Try<T> result = supplier.get();
            long durationInNanos = System.nanoTime() - start;
            if (result.isSuccess()) {
                circuitBreaker.onSuccess(durationInNanos, TimeUnit.NANOSECONDS);
                return result;
            } else {
                circuitBreaker
                    .onError(durationInNanos, TimeUnit.NANOSECONDS, result.getCause());
                return result;
            }
        } else {
            return Try.failure(
                CallNotPermittedException.createCallNotPermittedException(circuitBreaker));
        }
    };
}
 

/**
 * Returns the value of a particular row column as a specific type.
 * This method performs bounds checks and type checks. Any errors
 * will return a Try.failure.
 *
 * @param type The data type.
 * @param idx The index of the column.
 * @param <T> The value type.
 * @return Returns the value at the specified index.
 */
public <T> Try<T> tryGetAs(Class<T> type, Integer idx) {

    // Get the column as it's typed version.
    Try<DataColumn<T>> col = this.table.columns()
            .tryGet(idx)
            .flatMap(c -> c.asType(type));

    return col.isFailure()
            ? Try.failure(col.getCause())
            : Try.success(col.get().valueAt(this.rowIdx));
}
 

/**
 * Returns the value of a particular row column as a specific type.
 * This method performs bounds checks and type checks. Any errors
 * will return a Try.failure.
 *
 * @param type The data type.
 * @param colName The name of the column.
 * @param <T> The value type.
 * @return Returns the value at the specified index.
 */
public <T> Try<T> tryGetAs(Class<T> type, String colName) {

    // Get the column as it's typed version.
    Try<DataColumn<T>> col = this.table.columns()
            .tryGet(colName)
            .flatMap(c -> c.asType(type));

    return col.isFailure()
            ? Try.failure(col.getCause())
            : Try.success(col.get().valueAt(this.rowIdx));
}
 

/**
 * Returns a supplier which is decorated by a bulkhead.
 *
 * @param bulkhead the bulkhead
 * @param supplier the original supplier
 * @param <T>      the type of results supplied by this supplier
 * @return a supplier which is decorated by a Bulkhead.
 */
static <T> Supplier<Try<T>> decorateTrySupplier(Bulkhead bulkhead, Supplier<Try<T>> supplier) {
    return () -> {
        if (bulkhead.tryAcquirePermission()) {
            try {
                return supplier.get();
            } finally {
                bulkhead.onComplete();
            }
        } else {
            return Try.failure(BulkheadFullException.createBulkheadFullException(bulkhead));
        }
    };
}
 

/**
 * Creates a supplier which is restricted by a RateLimiter.
 *
 * @param rateLimiter the RateLimiter
 * @param permits     number of permits that this call requires
 * @param supplier    the original supplier
 * @param <T>         the type of results supplied supplier
 * @return a supplier which is restricted by a RateLimiter.
 */
static <T> Supplier<Try<T>> decorateTrySupplier(RateLimiter rateLimiter, int permits,
    Supplier<Try<T>> supplier) {
    return () -> {
        try {
            waitForPermission(rateLimiter, permits);
            return supplier.get();
        } catch (RequestNotPermitted requestNotPermitted) {
            return Try.failure(requestNotPermitted);
        }
    };
}
 

public Try<String> doSomethingErroneous() {
	assertTrue(TransactionSynchronizationManager.isActualTransactionActive());
	assertFalse(TransactionSynchronizationManager.isCurrentTransactionReadOnly());
	return Try.failure(new IllegalStateException());
}
 

public Try<String> doSomethingErroneousWithCheckedException() {
	assertTrue(TransactionSynchronizationManager.isActualTransactionActive());
	assertFalse(TransactionSynchronizationManager.isCurrentTransactionReadOnly());
	return Try.failure(new Exception());
}
 

@Transactional(rollbackFor = Exception.class)
public Try<String> doSomethingErroneousWithCheckedExceptionAndRollbackRule() {
	assertTrue(TransactionSynchronizationManager.isActualTransactionActive());
	assertFalse(TransactionSynchronizationManager.isCurrentTransactionReadOnly());
	return Try.failure(new Exception());
}
 

private Try<Object> columnToValue(Try<IDataColumn> column) {
    return column.isSuccess()
            ? Try.success(column.get().valueAt(this.rowIdx))
            : Try.failure(column.getCause());
}
 

/**
 * Used to perform a type check and cast on an object instance.
 * Returns a Try success or failure depending on if it was valid cast.
 *
 * @param <T> The type to return.
 * @param type The type to cast to.
 * @param obj The object to cast.
 * @return Returns a Success<T> or a Failure.
 */
@SuppressWarnings({"unchecked"})
static <T> Try<T> tryCast(Class<T> type, Object obj) {
    return type.isInstance(obj)
            ? Try.success((T)obj)
            : Try.failure(new DataTableException("Invalid cast."));
}
 

/**
 * Asserts the argument is not null. Returns in a Try.
 *
 * @param <T> The argument type.
 * @param argument The argument to check.
 * @param name The name of the argument.
 * @return Returns a Try testing the argument being null.
 */
public static <T> Try<T> tryNotNull(T argument, String name) {
    return argument == null
            ? Try.failure(new IllegalArgumentException("Invalid value [NULL] for argument " + name))
            : Try.success(argument);
}
 

/**
 * Creates a DataTableException wrapped in a Try.
 *
 * @param errorMessage The error message.
 * @param <T> The Try type.
 * @return Returns a new DataTable Exception in a try.
 */
public static <T> Try<T> tryError(String errorMessage) {
    return Try.failure(new DataTableException(errorMessage));
}
 

/**
 * Creates a DataTableException wrapped in a Try.
 *
 * @param errorMessage The error message.
 * @param throwable The inner exception.
 * @param <T> The Try type.
 * @return Returns a new DataTable Exception in a try.
 */
public static <T> Try<T> tryError(String errorMessage, Throwable throwable) {
    return Try.failure(new DataTableException(errorMessage, throwable));
}