opencms整站开发之五--- 调用opencms源码创建文件

在opencms中存两种基本的文件类型，一种是 File,另一种是 folder. 通常的JSP,HTML 就属于File类型。而文件夹只有一种，不用多说。这个两种文件都继承于 org.opencms.file.CmsResource 这个基类。CmsResource是opencms中最基本类型。创建它，也就是创建了File 或是 folder了。

要创建文件，我们必须了解opencms的核心工具类 org.opencms.file.CmsObject ,先摘录其源码的注释：

/* 
 * File   : $Source: /usr/local/cvs/opencms/src/org/opencms/file/CmsObject.java,v $ 
 * Date   : $Date: 2008-04-21 08:35:04 $ 
 * Version: $Revision: 1.163 $ 
 * 
 * This library is part of OpenCms - 
 * the Open Source Content Management System 
 * 
 * Copyright (c) 2002 - 2008 Alkacon Software GmbH (http://www.alkacon.com) 
 * 
 * This library is free software; you can redistribute it and/or 
 * modify it under the terms of the GNU Lesser General Public 
 * License as published by the Free Software Foundation; either 
 * version 2.1 of the License, or (at your option) any later version. 
 * 
 * This library 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 
 * Lesser General Public License for more details. 
 * 
 * For further information about Alkacon Software GmbH, please see the 
 * company website: http://www.alkacon.com 
 * 
 * For further information about OpenCms, please see the 
 * project website: http://www.opencms.org 
 *  
 * You should have received a copy of the GNU Lesser General Public 
 * License along with this library; if not, write to the Free Software 
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA 
 */ 

package org.opencms.file; 

import org.opencms.db.CmsDbEntryNotFoundException; 
import org.opencms.db.CmsPublishList; 
import org.opencms.db.CmsResourceState; 
import org.opencms.db.CmsSecurityManager; 
import org.opencms.db.CmsUserSettings; 
import org.opencms.file.history.CmsHistoryPrincipal; 
import org.opencms.file.history.CmsHistoryProject; 
import org.opencms.file.history.I_CmsHistoryResource; 
import org.opencms.file.types.I_CmsResourceType; 
import org.opencms.lock.CmsLock; 
import org.opencms.lock.CmsLockFilter; 
import org.opencms.lock.CmsLockType; 
import org.opencms.main.CmsException; 
import org.opencms.main.CmsIllegalArgumentException; 
import org.opencms.main.I_CmsEventListener; 
import org.opencms.main.OpenCms; 
import org.opencms.relations.CmsRelationFilter; 
import org.opencms.relations.CmsRelationType; 
import org.opencms.report.CmsShellReport; 
import org.opencms.report.I_CmsReport; 
import org.opencms.security.CmsAccessControlEntry; 
import org.opencms.security.CmsAccessControlList; 
import org.opencms.security.CmsOrganizationalUnit; 
import org.opencms.security.CmsPermissionSet; 
import org.opencms.security.CmsPrincipal; 
import org.opencms.security.CmsRole; 
import org.opencms.security.CmsRoleViolationException; 
import org.opencms.security.CmsSecurityException; 
import org.opencms.security.I_CmsPermissionHandler; 
import org.opencms.security.I_CmsPrincipal; 
import org.opencms.util.CmsUUID; 
import org.opencms.workplace.CmsWorkplace; 

import java.util.Collections; 
import java.util.HashMap; 
import java.util.List; 
import java.util.Map; 
import java.util.Set; 

/** 
 * This pivotal class provides all authorized access to the OpenCms VFS resources.<p> 
 *  
 * It encapsulates user identification and permissions. 
 * Think of it as an initialized "shell" to access the OpenCms VFS. 
 * Every call to a method here will be checked for user permissions 
 * according to the <code>{@link org.opencms.file.CmsRequestContext}</code> this CmsObject instance was created with.<p> 
 *  
 * From a JSP page running in OpenCms, use <code>{@link org.opencms.jsp.CmsJspBean#getCmsObject()}</code> to gain  
 * access to the current users CmsObject. Usually this is done with a <code>{@link org.opencms.jsp.CmsJspActionElement}</code>.<p> 
 *  
 * To generate a new instance of this class in your application, use  
 * <code>{@link org.opencms.main.OpenCms#initCmsObject(String)}</code>. The argument String should be  
 * the name of the guest user, usually "Guest" and more formally obtained by <code>{@link org.opencms.db.CmsDefaultUsers#getUserGuest()}</code>. 
 * This will give you an initialized context with guest user permissions. 
 * Then use <code>{@link CmsObject#loginUser(String, String)}</code> to log in the user you want. 
 * Obviously you need the password for the new user. 
 * You should never try to create an instance of this class using the constructor,  
 * this is reserved for internal operation only.<p>  
 * 
 * @author Alexander Kandzior  
 * @author Thomas Weckert   
 * @author Carsten Weinholz  
 * @author Andreas Zahner  
 * @author Michael Moossen  
 *  
 * @version $Revision: 1.163 $ 
 *  
 * @since 6.0.0  
 */ 
public final class CmsObject { 

    /** The request context. */ 
    protected CmsRequestContext m_context; 

    /** The security manager to access the cms. */ 
    protected CmsSecurityManager m_securityManager;

从第一句不难看出，些类提供了对 opencms VFS(虚拟文件系统）合法，授权访问。

他提供了很多创建，删除，修改VFS的方法。

 /** 
     * Creates a new resource of the given resource type 
     * with the provided content and properties.<p> 
     *  
     * @param resourcename the name of the resource to create (full current site relative path) 
     * @param type the type of the resource to create 
     * @param content the contents for the new resource 
     * @param properties the properties for the new resource 
     *  
     * @return the created resource 
     *  
     * @throws CmsException if something goes wrong 
     * @throws CmsIllegalArgumentException if the <code>resourcename</code> argument is null or of length 0 
     */ 
    public CmsResource createResource(String resourcename, int type, byte[] content, List properties) 
    throws CmsException, CmsIllegalArgumentException { 

        return getResourceType(type).createResource(this, m_securityManager, resourcename, content, properties); 
    }

上面的代码片断，就是其创建 CmsResource 方法。当然，这只是一个高度抽象的API接口，内部层层调用了很多工厂提供的方法来创建资源。最底层是利用JDBC 创建了一条记录插入数据库。

要调用CmsObject 所提供的方法来进行自己的操作.我们必须先得到CmsObject 实例.你可在opencms正常执行的某一环节进来获取CmsObject. 或可以在自己创建. 下面是在 jsp 中的创建方法:

    org.opencms.jsp.CmsJspActionElement cms = new org.opencms.jsp.CmsJspActionElement( 
            pageContext, request, response); 
    CmsObject cobject = cms.getCmsObject(); 

得到了CmsObject实例对象,你可以进行自己的操作了.

下面是我写的一个工具类的方法:

/** 
     * * 创建一个CmsResource 
     *  
     * @param cms 
     *            CmsObject 
     * @param fullResourceName 
     *            文件的相对路径 比如从根目录开始: module1/news1/news_9999.html 
     * @param content 
     *            二进度形式的字节文件 可以为空 
     * @param fileType 
     *            要创建的文件类型 比如 "jsp"  最后会转换成类型对应的ID 如我以前写的文章里所定义的 7800 
     * @param properties 
     *            相关属性 你可以在list加入一些CmsProperty来为些文件设置相关属性 null 
     * @return 创建的CmsResource 
     *  
     */ 
    public static CmsResource createFile(CmsObject cms, 
            String fullResourceName, byte[] content, String fileType, 
            List<CmsProperty> properties) { 
        CmsResource cmsResource = null; 
        try { 

            /** 
             * 类型 
             */ 
            I_CmsResourceType resType = OpenCms.getResourceManager() 
                    .getResourceType(fileType); 

            cmsResource = cms.createResource(fullResourceName, resType 
                    .getTypeId(), content, properties); 

        } catch (CmsException e) { 
            LOG.error("CmsException", e); 
        } catch (Exception e) { 
            LOG.error("Exception", e); 
        } 
        return cmsResource; 

    }

CmsProperty可以用下面的方法创建:

    /** 
     * 创建一个属性对象 
     *  
     * @param name 
     * @param value 
     */ 
    public static CmsProperty generatePropertie(String name, String value) { 

        CmsProperty prop = new CmsProperty(); 
        prop.setAutoCreatePropertyDefinition(true); 
        prop.setName(name); 
        prop.setValue(value, CmsProperty.TYPE_SHARED); 
        return prop; 

    }