jahiatools.java

java 写的一个新闻发布系统

     }



    //-------------------------------------------------------------------------
    /**
     * Return a substitute String value if the source is null otherwise
     * return the source value
     *
     * @param String the data
     * @param String the subsitute value
     * @return String
     * @author NK
     */
     static public String replaceNullString(String data, String newValue){
        if ( data != null ){
            return data;
        }
        return newValue;
     }


    //-------------------------------------------------------------------------
    /**
     * Return a substitute Integer object if the source is null otherwise
     * return the source integer object
     *
     * @param Integer data
     * @param Integer newValue
     * @return String
     * @author NK
     */
     static public Integer replaceNullInteger(Integer data, Integer newValue){
        if ( data != null ){
            return data;
        }
        return newValue;
     }


    //-------------------------------------------------------------------------
    /**
     * Guarantee a String not to be null, giving it an empty value if needed.
     *
     * @author Mikha雔 Janson
     * @param   inputString      A <code>String</code> value, that may be null
     *
     * @return  a <code>String</code> value, guaranteed not to be null.
     */
    public static String nnString( String inputString )
    {
        String outputString  = (inputString != null) ? inputString : "";
        return outputString;
    } // end nnString


    //-------------------------------------------------------------------------
    /**
     * Simple <code>int</code> to <code>boolean</code> converter
     *
     * @param value an integer value
     * @return <code>false</code> if <code>0</code>, <code>1</code> if not <code>0</code>
     */
    static public boolean int2boolean(int value)
    {
        return value != 0;
    }


    //-------------------------------------------------------------------------
    /**
     * Simple <code>boolean</code> to <code>int</code> converter
     *
     * @param value a <code>boolean</code> value
     * @return <code>0</code> if <code>false</code>, <code>1</code> if <code>true</code>
     */
    static public int boolean2int(boolean value)
    {
        return value ? 1 : 0;
    }


    //-------------------------------------------------------------------------
    /**
     * Method inverseVector : inverse the elements contained in a vector
     *
     * @param myVector   the vector to inverse
     * @return  the inversed vector
     */
    static public Vector inverseVector(Vector myVector) {

        Vector temp = new Vector();
        for(int i = myVector.size()-1; i >= 0; i--) {

            temp.addElement(myVector.get(i));
        }
        return temp;
    }


    //-------------------------------------------------------------------------
    /**
     * Update a property's value in a properties file.
     *
     * @author  Khue N'Guyen
     * @author  Alexandre Kraft
     *
     * @param   name    the property name
     * @param   val     the property value
     * @param   path    the full filesystem path to the properties file
     */
    public static void updatepropvalue( String propertyName,
                                            String propvalue,
                                            String path )
    {
        Vector  bufferVector  = new Vector();
        String  lineReaded    = null;
        int     position      = 0;
        boolean lineFound     = false;
        boolean success       = false;

        try
        {
            // parse the file...
            BufferedReader buffered  = new BufferedReader( new FileReader(path) );
            while((lineReaded = buffered.readLine()) != null) {
                if(lineReaded.indexOf(propertyName) >= 0) {
                    position = lineReaded.lastIndexOf("=");
                    if(position >= 0) {
                        bufferVector.add( lineReaded.substring(0,position+1) + "   " + propvalue );
                        lineFound = true;
                    }
                } else {
                    bufferVector.add(lineReaded);
                }
            }
            buffered.close();

            // add property if it don't exists before...
            if(!lineFound)
            {
                bufferVector.add( propertyName + " =   " + propvalue );
            }

            // rewrite the file...
            File         thisFile      = new File(path);
            FileWriter   fileWriter    = new FileWriter( thisFile );
            StringBuffer outputBuffer  = new StringBuffer();

            for(int i=0; i < bufferVector.size(); i++) {
                outputBuffer.append((String) bufferVector.get(i));
            }

            fileWriter.write( outputBuffer.toString() );
            fileWriter.close();
        } catch (java.io.IOException ioe) {
        }
    } // end updatepropvalue



    /**************************************************************************
     * Client Browser Check Tools
     *
     **************************************************************************/

    //-------------------------------------------------------------------------
    public static boolean isMSIExplorer(HttpServletRequest req){
        return ( req.getHeader("user-agent") != null && req.getHeader("user-agent").indexOf("MSIE") != -1 );
    }

    //-------------------------------------------------------------------------
    public static boolean isLynx(HttpServletRequest req){
        return ( req.getHeader("user-agent") != null && req.getHeader("user-agent").indexOf("Lynx") != -1 );
    }



    /**************************************************************************
     * Servlet Request Parameters handling
     *
     **************************************************************************/

    //-------------------------------------------------------------------------
    /**
     * return a parameter of String type if not null or return the subsitute value
     *
     * @param HttpServletRequest req the request object
     * @param String the param name
     * @param String the subsitute value to return if the parameter is null
     * @return String the parameter value
     * @author NK
     */
    public static String getStrParameter(HttpServletRequest req, String paramName, String nullVal){

        String val = (String)req.getParameter(paramName);
        if ( val == null ){
            return nullVal;
        }
        return val;
    }


    //-------------------------------------------------------------------------
    /**
     * return a parameter of Integer type if not null or return the subsitute value
     *
     * @param HttpServletRequest req the request object
     * @param String the param name
     * @param Integer the subsitute value to return if the parameter is null
     * @return Integer the parameter value
     * @author NK
     */
    public static Integer getIntParameter(HttpServletRequest req, String paramName, Integer nullVal){

        String strVal = (String)req.getParameter(paramName);
        Integer val = null;
        if ( strVal == null ){
            return nullVal;
        } else {
            try {
                val = new Integer(strVal);
            } catch ( Throwable t ){
                val = nullVal;
            }
        }
        return val;
    }



    //-------------------------------------------------------------------------
   /**
     * Remove context attribute they names start with the string passed in
     * parameter. In details, this method select which attribute he wants to
     * remove and compose a temporary vector with it. Next step is to delete
     * all attributes contains in this vector, via an enumeration. The reason
     * of this is that you can't remove a context attribute while you use the
     * getAttributeNames method to get the list of context attribute names.
     * @author Alexandre Kraft
     *
     * @param  context      The context where do you want to remove attributes
     * @param  startString  The string for select the attributes by they names.
     */
    public static void removeContextAttributes( ServletContext context,
                                                String         startString )
    {
        Enumeration contextAttributeNames =  context.getAttributeNames();
        Vector      attributesToRemove    =  new Vector();
        String      attributeName;

        while(contextAttributeNames.hasMoreElements()) {
            attributeName =  (String) contextAttributeNames.nextElement();
            if(attributeName.length() >= 36) {
                if((attributeName.substring(0,36).equals(startString)) && (attributeName.indexOf("accessGranted") == -1)) {
                    attributesToRemove.add( attributeName );
                }
            }
        }

        Enumeration attributesListToRemove =  attributesToRemove.elements();
        while(attributesListToRemove.hasMoreElements()) {
            attributeName =  (String) attributesListToRemove.nextElement();
            context.removeAttribute( attributeName );
        }
    } // end removeContextAttributes


    /**************************************************************************
     * HTML Tools
     *
     *
     *************************************************************************/

    //-------------------------------------------------------------------------
   /***
      * Return text with HTML entities (text2html)
      * @author POL
      * @version 1.0   POL 14/06/2001
      * @version 1.1   MAP 23.10.2001
      * @param  str    Input String
      * @return str    HtmlEntities output
      */
    public static String text2html( String str )
    {
        return TextHtml.text2html(str); // Changed by MAP
    }

    //-------------------------------------------------------------------------
   /***
      * Return text without HTML entities (html2text)
      * @author POL
      * @version 1.0   POL 18/06/2001
      * @version 1.1   MAP 23.10.2001
      * @param  str    Input String
      * @return str    Text output
      */
    public static String html2text(String str)
    {
        str = replacePattern(str,"X-AND-X","&amp;");
        str = replacePattern(str,"&amp;","&");
        return TextHtml.html2text(str); // Changed by MAP
    }


    //-------------------------------------------------------------------------
   /***
      * text2XMLEntityRef
      * Parse a text and replace XML specific characters to their XML Entity Reference value.
      * @author Khue Nguyen
      * @param  str    Input String
      * @param  invert    int (0/1) 0 : text to XML Entity Reference / 1 : XML Entity Reference to text
      * @return str    Text output
      */
    public static String text2XMLEntityRef(String str, int invert)
    {
        if ( str == null || str.trim().equals("") ){
            return str;
        }
        if (invert == 0) {  // Change by MAP
            str = TextHtml.text2html(str);
        }
        else {
            str = TextHtml.html2text(str);
        }
        str = replacePattern(str,"&","&amp;",invert);
        str = replacePattern(str,"<","&lt;",invert);
        str = replacePattern(str,">","&gt;",invert);
        str = replacePattern(str,"\"","&quot;",invert);
        str = replacePattern(str,"'","&apos;",invert);
        return str;
    }


    //-------------------------------------------------------------------------
    /**
     * Tests whether an URL is valid or not.
     *
     * @param URLString the String representation of the URL to test
     * @return <code>true</code> if the URL could be accessed; <code>false</code>
     * otherwise
     */
    public static boolean isValidURL(String URLString) {
        try {
            URL testURL = new URL(URLString);
            testURL.openConnection();
            return true;
        } catch (Exception e) {
            return false;
        }
    }

} // end JahiaTools