/*
 * @(#)Diagnostic.java	1.5 06/09/25
 *
 * Copyright 2006 Sun Microsystems, Inc. All rights reserved.
 * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */

package javax.tools;

import java.util.Locale;

/**
 * Interface for diagnostics from tools.  A diagnostic usually reports
 * a problem at a specific position in a source file.  However, not
 * all diagnostics are associated with a position or a file.
 *
 * <p>A position is a zero-based character offset from the beginning of
 * a file.  Negative values (except {@link #NOPOS}) are not valid
 * positions.
 *
 * <p>Line and column numbers begin at 1.  Negative values (except
 * {@link #NOPOS}) and 0 are not valid line or column numbers.
 *
 * @param <S> the type of source object used by this diagnostic
 *
 * @author Peter von der Ahé
 * @author Jonathan Gibbons
 * @since 1.6
 */
public interface Diagnostic<S> {

    /**
     * Kinds of diagnostics, for example, error or warning.
     */
    enum Kind {
        /**
         * Problem which prevents the tool's normal completion.
         */
        ERROR,
        /**
         * Problem which does not usually prevent the tool from
         * completing normally.
         */
        WARNING,
        /**
         * Problem similar to a warning, but is mandated by the tool's
         * specification.  For example, the Java™ Language
         * Specification, 3rd Ed. mandates warnings on certain
         * unchecked operations and the use of deprecated methods.
         */
        MANDATORY_WARNING,
        /**
         * Informative message from the tool.
         */
        NOTE,
        /**
         * Diagnostic which does not fit within the other kinds.
         */
        OTHER,
    }

    /**
     * Used to signal that no position is available.
     */
    public final static long NOPOS = -1;

    /**
     * Gets the kind of this diagnostic, for example, error or
     * warning.
     * @return the kind of this diagnostic
     */
    Kind getKind();

    /**
     * Gets the source object associated with this diagnostic.
     *
     * @return the source object associated with this diagnostic.
     * {@code null} if no source object is associated with the
     * diagnostic.
     */
    S getSource();

    /**
     * Gets a character offset from the beginning of the source object
     * associated with this diagnostic that indicates the location of
     * the problem.  In addition, the following must be true:
     *
     * <p>{@code getStartPostion() <= getPosition()}
     * <p>{@code getPosition() <= getEndPosition()}
     *
     * @return character offset from beginning of source; {@link
     * #NOPOS} if {@link #getSource()} would return {@code null} or if
     * no location is suitable
     */
    long getPosition();

    /**
     * Gets the character offset from the beginning of the file
     * associated with this diagnostic that indicates the start of the
     * problem.