io.dropwizard.jersey.params.AbstractParam Maven / Gradle / Ivy
package io.dropwizard.jersey.params;
import io.dropwizard.jersey.errors.ErrorMessage;
import jakarta.ws.rs.WebApplicationException;
import jakarta.ws.rs.core.MediaType;
import jakarta.ws.rs.core.Response;
import jakarta.ws.rs.core.Response.Status;
import org.checkerframework.checker.nullness.qual.Nullable;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* An abstract base class from which to build Jersey parameter classes.
*
* @param the type of value wrapped by the parameter
*/
public abstract class AbstractParam {
private static final Logger LOGGER = LoggerFactory.getLogger(AbstractParam.class);
private final String parameterName;
private final T value;
/**
* Given an input value from a client, creates a parameter wrapping its parsed value.
*
* @param input an input value from a client request, might be {@code null}
*/
protected AbstractParam(@Nullable String input) {
this(input, "Parameter");
}
/**
* Given an input value from a client, creates a parameter wrapping its parsed value.
*
* @param input an input value from a client request, might be {@code null}
* @param parameterName name of the parameter with the provided value
*/
protected AbstractParam(@Nullable String input, String parameterName) {
this.parameterName = parameterName;
try {
this.value = parse(input);
} catch (final Exception e) {
final ErrorMessage message = generateErrorMessage(input, e);
throw new WebApplicationException(message.getMessage(), message.getCode());
}
}
/**
* Generates an {@code ErrorMessage} to return to the client.
*
* @param input the raw input value
* @param e the exception thrown while parsing {@code input}
* @return the {@code ErrorMessage} with the message and status to return to the client
*/
protected ErrorMessage generateErrorMessage(@Nullable String input, Exception e) {
// maintains backwards compatibility if deprecated error(String, Exception) method is overridden
final Response response = error(input, e);
if (response != null) {
throw new WebApplicationException(response);
}
LOGGER.debug("Invalid input received: {}", input);
String errorMessage = errorMessage(e);
if (errorMessage.contains("%s")) {
errorMessage = String.format(errorMessage, parameterName);
}
return new ErrorMessage(getErrorStatus().getStatusCode(), errorMessage);
}
/**
* Deprecated - instead of throwing a {@link WebApplicationException} that contains a response with an entity,
* AbstractParam now throws a {@link WebApplicationException} that contains a message and status code,
* and can be mapped to a response using exception mappers. This method is kept for backwards compatibility with
* user-defined AbstractParam implementations that implement custom error behavior by overriding this method.
*
* Given a string representation which was unable to be parsed and the exception thrown, produce
* a {@link Response} to be sent to the client.
*
* @param input the raw input value
* @param e the exception thrown while parsing {@code input}
* @return the {@link Response} to be sent to the client, or {@code null} to allow AbstractParam to throw
* a {@code WebApplicationException} that contains a message and status code.
* @deprecated instead of returning a {@link Response} from this method, subclasses should override
* {@link #errorMessage} and {@link #getErrorStatus} to allow a {@link WebApplicationException} to be thrown
* which is mapped to a response using the exception mappers.
*/
@Nullable
@Deprecated
protected Response error(@Nullable String input, Exception e) {
return null;
}
/**
* Deprecated - the media type should be set by the exception mapper instead. This method is no longer called
* by AbstractParam.
*
* @return not used
* @deprecated the media type should be set by the exception mapper instead
*/
@Deprecated
protected MediaType mediaType() {
return MediaType.APPLICATION_JSON_TYPE;
}
/**
* Given a string representation which was unable to be parsed and the exception thrown, produce
* an error message to be sent to the client.
*
* @param e the exception thrown while parsing {@code input}
* @return the error message to be sent the client
*/
protected String errorMessage(Exception e) {
return String.format("%s is invalid: %s", parameterName, e.getMessage());
}
/**
* Given a string representation which was unable to be parsed, produce a {@link Status} for the
* {@link Response} to be sent to the client.
*
* @return the HTTP {@link Status} of the error message
*/
@SuppressWarnings("MethodMayBeStatic")
protected Status getErrorStatus() {
return Status.BAD_REQUEST;
}
/**
* Given a string representation, parse it and return an instance of the parameter type.
*
* @param input the raw input
* @return {@code input}, parsed as an instance of {@code T}
* @throws Exception if there is an error parsing the input
*/
protected abstract T parse(@Nullable String input) throws Exception;
/**
* Returns the underlying value.
*
* @return the underlying value
*/
public T get() {
return value;
}
@Override
public boolean equals(Object obj) {
if (this == obj) {
return true;
}
if ((obj == null) || (getClass() != obj.getClass())) {
return false;
}
final AbstractParam that = (AbstractParam) obj;
return value.equals(that.value);
}
@Override
public int hashCode() {
return value.hashCode();
}
@Override
public String toString() {
return value.toString();
}
}