HtmlParserMessage.java

// Copyright � 2002-2005 Canoo Engineering AG, Switzerland.
package com.canoo.webtest.steps;

import com.gargoylesoftware.htmlunit.html.HTMLParserListener;

import java.net.URL;
import java.util.ArrayList;
import java.util.List;

/**
 * Represents a message generated by an html parser.
 * @author Marc Guillemot
 */
public class HtmlParserMessage implements Comparable
{
    /**
     * Safe enum to represent the type of a message.
     */
    public static final class Type implements Comparable
    {
        public static final String ERROR_NAME = "error";
        public static final String WARNING_NAME = "warning";
        public static final Type ERROR = new Type(ERROR_NAME);
        public static final Type WARNING = new Type(WARNING_NAME);
        private String fName;

        /**
         * Private constructor to prohibit external instantiations
         * @param str
         */
        private Type(final String str) {
            fName = str;
        }

        /**
         * Compares with following rule: error > warning
         * (no need to override equals(): in this case it is equivalent to ==)
         *
         * @throws ClassCastException if the argument is not a {@link HtmlParserMessage.Type}
         */
        public int compareTo(final Object o) {
            final Type other = (Type) o;
            if (getName().equals(other.getName()))
                return 0;
            else
                return isError() ? 1 : -1;
        }

        /**
         * Gets the name of the type
         */
        public String getName() {
            return fName;
        }

        public boolean isError() {
            return ERROR_NAME.equals(getName());
        }

        public boolean isWarning() {
            return WARNING_NAME.equals(getName());
        }

        /**
         * Gets the name.
         */
        public String toString() {
            return getName();
        }
    }


    /**
     * Listener collecting the messages from parser.
     */
    public static class MessageCollector implements HTMLParserListener
    {
        private List<HtmlParserMessage> fMessages = new ArrayList<HtmlParserMessage>();
        public void error(final String message, final URL url, final int line, final int column, final String key) {
            fMessages.add(new HtmlParserMessage(Type.ERROR, url, message, line, column));
        }
        public void warning(final String message, final URL url, final int line, final int column, final String key) {
            fMessages.add(new HtmlParserMessage(Type.WARNING, url, message, line, column));
        }
        /**
         * Gets all messages received since last call to this method.
         * @return a list of {@link HtmlParserMessage}
         */
        public List popAll() {
            final List l = fMessages;
            fMessages = new ArrayList<HtmlParserMessage>();
            return l;
        }
    }

    private int fColumn;
    private int fLine;
    private String fMessage;
    private Type fType;
    private URL fUrl;
    private volatile int fHash;

    public HtmlParserMessage(final Type type, final URL url, final String strMessage,
                             final int iLine, final int iColumn) {
        fType = type;
        fUrl = url;
        fMessage = strMessage;
        fLine = iLine;
        fColumn = iColumn;
    }

    /**
     * Compare to an other HtmlParserMessage according to (url, line, col, type, msg)
     * @see java.lang.Comparable#compareTo(java.lang.Object)
     */
    public int compareTo(final Object o) {
        final HtmlParserMessage other = (HtmlParserMessage) o;

        // first compare urls
        int iRep = getURL().toString().compareTo(other.getURL().toString());
        if (iRep != 0)
            return iRep;

        // then line in file
        iRep = getLine() - other.getLine();
        if (iRep != 0)
            return iRep;

        // then column in line
        iRep = getColumn() - other.getColumn();
        if (iRep != 0)
            return iRep;

        // error or warning
        iRep = getType().compareTo(other.getType());
        if (iRep != 0)
            return iRep;

        // and at least the message
        return getMessage().compareTo(other.getMessage());
    }

    public int hashCode() {
        if (fHash == 0) fHash = calculateHash();
        return fHash;
    }

    private int calculateHash() {
        // aggregate of primes multiplied by hashes of components
        final int h1 = 3 * new Integer(fColumn).hashCode();
        final int h2 = 5 * new Integer(fLine).hashCode();
        final int h3 = 7 * fMessage.hashCode();
        final int h4 = 11 * fType.hashCode();
        final int h5 = 13 * fUrl.hashCode();
        return h1 + h2 + h3 + h4 + h5;
    }

    /**
     * Test for equality with an other HtmlParserMessage according to (url, line, col, type, msg)
     * @see java.lang.Object#equals(java.lang.Object)
     */
    public boolean equals(final Object o) {
        return compareTo(o) == 0;
    }

    /**
     * Gets the column in the source file for which the message has been generated
     */
    public int getColumn() {
        return fColumn;
    }

    /**
     * Gets the line in the source file for which the message has been generated
     */
    public int getLine() {
        return fLine;
    }

    /**
     * Gets the description of the message
     */
    public String getMessage() {
        return fMessage;
    }

    /**
     * Gets the type of the message determining its severity
     */
    public Type getType() {
        return fType;
    }

    /**
     * Gets the url of the file which parsing caused this message.
     */
    public URL getURL() {
        return fUrl;
    }
}