com.liusoft.dlog4j.TextCacheManager.java Source code

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Here is the source code for com.liusoft.dlog4j.TextCacheManager.java

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/*
 *  TextCacheManager.java
 *  
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU Library General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 *  
 *  Author: Winter Lau
 *  http://dlog4j.sourceforge.net
 *  2006-5-12
 */
package com.liusoft.dlog4j;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.FileReader;
import java.io.IOException;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import com.liusoft.dlog4j.util.StringUtils;

/**
 * ?
 * {base}/{type}/{id/10000}/id.htm
 * @author liudong
 * @call_by 
 */
public class TextCacheManager {

    private final static Log log = LogFactory.getLog(TextCacheManager.class);

    private static String basePath;

    /**
     * ?
     * @param arg0
     */
    public synchronized static void init(String arg0) {
        if (basePath == null) {
            if (!StringUtils.equals("/", File.separator))
                basePath = StringUtils.replace(arg0, "/", File.separator);
            else
                basePath = arg0;
            if (!basePath.endsWith(File.separator))
                basePath += File.separator;
            File f = new File(basePath);
            if (!f.exists())
                f.mkdirs();
        }
    }

    /**
     * ????
     * @param type
     * @param id
     * @return
     */
    public static String getTextContent(int type, long id) {
        String path = getFilePath(type, id);
        BufferedReader br = null;
        StringBuffer text = new StringBuffer();
        try {
            String line_sep = System.getProperty("line.separator");
            if (line_sep == null)
                line_sep = "\r\n";
            br = new BufferedReader(new FileReader(path));
            do {
                String line = br.readLine();
                if (line == null)
                    break;
                text.append(line);
                text.append(line_sep);
            } while (true);
            return text.toString();
        } catch (FileNotFoundException e) {
        } catch (IOException e) {
            log.error("Exception occur when reading " + path, e);
        } finally {
            if (br != null) {
                try {
                    br.close();
                } catch (IOException e) {
                }
            }
            text = null;
        }
        return null;
    }

    /**
     * 
     * @param type
     * @param id
     * @param text
     */
    public static void updateTextContent(int type, long id, String text) {
        if (text == null)
            return;
        String path = getFilePath(type, id);
        FileOutputStream fos = null;
        try {
            File f = new File(path);
            if (!f.getParentFile().exists())
                f.getParentFile().mkdirs();
            fos = new FileOutputStream(f);
            fos.write(text.getBytes());
        } catch (IOException e) {
            log.error("Exception occur when writing to " + path, e);
        } finally {
            if (fos != null) {
                try {
                    fos.close();
                } catch (Exception e) {
                }
            }
        }
    }

    /**
     * 
     * @param type
     * @param id
     * @return
     */
    public static boolean deleteTextContent(int type, long id) {
        String path = getFilePath(type, id);
        return new File(path).delete();
    }

    /**
     * ?
     * @param type
     * @param id
     * @return
     */
    protected static String getFilePath(int type, long id) {
        StringBuffer sb = new StringBuffer(basePath);
        sb.append(type);
        sb.append(File.separator);
        sb.append(id / 10000);
        sb.append(File.separator);
        sb.append(id);
        sb.append(".htm");
        return sb.toString();
    }

}