RequestException.java

/*******************************************************************************
 *  Copyright (c) 2011 GitHub Inc.
 *  All rights reserved. This program and the accompanying materials
 *  are made available under the terms of the Eclipse Public License v1.0
 *  which accompanies this distribution, and is available at
 *  http://www.eclipse.org/legal/epl-v10.html
 *
 *  Contributors:
 *    Kevin Sawicki (GitHub Inc.) - initial API and implementation
 *******************************************************************************/
package org.eclipse.egit.github.core.client;

import static org.eclipse.egit.github.core.FieldError.CODE_ALREADY_EXISTS;
import static org.eclipse.egit.github.core.FieldError.CODE_INVALID;
import static org.eclipse.egit.github.core.FieldError.CODE_MISSING_FIELD;

import java.io.IOException;
import java.text.MessageFormat;
import java.util.List;

import org.eclipse.egit.github.core.FieldError;
import org.eclipse.egit.github.core.RequestError;

/**
 * Request exception class that wraps a {@link RequestError} object.
 */
public class RequestException extends IOException {

	private static final String FIELD_INVALID_WITH_VALUE = "Invalid value of ''{0}'' for ''{1}'' field"; //$NON-NLS-1$

	private static final String FIELD_INVALID = "Invalid value for ''{0}'' field"; //$NON-NLS-1$

	private static final String FIELD_MISSING = "Missing required ''{0}'' field"; //$NON-NLS-1$

	private static final String FIELD_ERROR = "Error with ''{0}'' field in {1} resource"; //$NON-NLS-1$

	private static final String FIELD_EXISTS = "{0} resource with ''{1}'' field already exists"; //$NON-NLS-1$

	/**
	 * serialVersionUID
	 */
	private static final long serialVersionUID = 1197051396535284852L;

	private final RequestError error;
	private final int status;

	/**
	 * Create request exception
	 *
	 * @param error
	 * @param status
	 */
	public RequestException(RequestError error, int status) {
		super();
		this.error = error;
		this.status = status;
	}

	public String getMessage() {
		return error != null ? formatErrors() : super.getMessage();
	}

	/**
	 * Get error
	 *
	 * @return error
	 */
	public RequestError getError() {
		return error;
	}

	/**
	 * Get status
	 *
	 * @return status
	 */
	public int getStatus() {
		return status;
	}

	/**
	 * Format field error into human-readable message
	 *
	 * @param error
	 * @return formatted field error
	 */
	protected String format(FieldError error) {
		String code = error.getCode();
		String value = error.getValue();
		String field = error.getField();

		if (CODE_INVALID.equals(code))
			if (value != null)
				return MessageFormat.format(FIELD_INVALID_WITH_VALUE, value,
						field);
			else
				return MessageFormat.format(FIELD_INVALID, field);

		if (CODE_MISSING_FIELD.equals(code))
			return MessageFormat.format(FIELD_MISSING, field);

		if (CODE_ALREADY_EXISTS.equals(code))
			return MessageFormat.format(FIELD_EXISTS, error.getResource(),
					field);

		// Use field error message as is if custom code
		if (FieldError.CODE_CUSTOM.equals(code)) {
			String message = error.getMessage();
			if (message != null && message.length() > 0)
				return message;
		}

		return MessageFormat.format(FIELD_ERROR, field, error.getResource());
	}

	/**
	 * Format all field errors into single human-readable message.
	 *
	 * @return formatted message
	 */
	public String formatErrors() {
		String errorMessage = error.getMessage();
		if (errorMessage == null)
			errorMessage = ""; //$NON-NLS-1$
		StringBuilder message = new StringBuilder(errorMessage);
		if (message.length() > 0)
			message.append(' ').append('(').append(status).append(')');
		else
			message.append(status);
		List<FieldError> errors = error.getErrors();
		if (errors != null && errors.size() > 0) {
			message.append(':');
			for (FieldError fieldError : errors)
				message.append(' ').append(format(fieldError)).append(',');
			message.deleteCharAt(message.length() - 1);
		}
		return message.toString();
	}
}