java Berkeley DB数据库操作，berkeleydb,Berkeley DB

java Berkeley DB数据库操作，berkeleydb,Berkeley DB

Berkeley DB Java Edition数据库操作

[Java]代码

package cn.outofmemory.demos.bdb;import java.io.File;import com.sleepycat.je.Cursor;import com.sleepycat.je.Database;import com.sleepycat.je.DatabaseConfig;import com.sleepycat.je.DatabaseEntry;import com.sleepycat.je.Environment;import com.sleepycat.je.EnvironmentConfig;import com.sleepycat.je.LockMode;import com.sleepycat.je.OperationStatus;import com.sleepycat.je.Transaction;import com.sleepycat.je.TransactionConfig;/* * 数据库操作类 */public class BDB {    private static Database bdb; // 数据源    private static Environment exampleEnv;// 环境对象    private static boolean isrunning = false;// 判断是否运行    /**     * 打开数据库方法     */    public static void start(String path) {        if (isrunning) {            return;        }        /******************** 文件处理 ***********************/        File envDir = new File(path);// 操作文件        if (!envDir.exists())// 判断文件路径是否存在，不存在则创建        {            envDir.mkdir();// 创建        }        /******************** 环境配置 ***********************/        EnvironmentConfig envConfig = new EnvironmentConfig();        envConfig.setTransactional(false); // 不进行事务处理        envConfig.setAllowCreate(true); // 如果不存在则创建一个        exampleEnv = new Environment(envDir, envConfig);// 通过路径，设置属性进行创建        /******************* 创建适配器对象 ******************/        DatabaseConfig dbConfig = new DatabaseConfig();        dbConfig.setTransactional(false); // 不进行事务处理        dbConfig.setAllowCreate(true);// 如果不存在则创建一个        dbConfig.setSortedDuplicates(true);// 数据分类        bdb = exampleEnv.openDatabase(null, "simpleDb", dbConfig); // 使用适配器打开数据库        isrunning = true; // 设定是否运行    }    /**     * 关闭数据库方法     */    public static void stop() {        if (isrunning) {            isrunning = false;            bdb.close();            exampleEnv.close();        }    }    public static boolean isrunning() {        return isrunning;    }    /**     * 数据存储方法 set(Here describes this method function with a few words)     *      * TODO(Here describes this method to be suitable the condition - to be     * possible to elect)     *      * @param key     * @param data     *      *            void     */    public static void set(byte[] key, byte[] data) {        DatabaseEntry keyEntry = new DatabaseEntry();        DatabaseEntry dataEntry = new DatabaseEntry();        keyEntry.setData(key); // 存储数据        dataEntry.setData(data);        OperationStatus status = bdb.put(null, keyEntry, dataEntry);// 持久化数据        if (status != OperationStatus.SUCCESS) {            throw new RuntimeException("Data insertion got status " + status);        }    }    /*     * 执行获取,根据key值获取     */    public static void selectByKey(String aKey) {        DatabaseEntry theKey =null;        DatabaseEntry theData = new DatabaseEntry();        try {             theKey = new DatabaseEntry(aKey.getBytes("utf-8"));        } catch (Exception e) {            // TODO Auto-generated catch block            e.printStackTrace();        }        if (bdb.get(null,theKey, theData,                LockMode.DEFAULT) == OperationStatus.SUCCESS) { //根据key值，进行数据查询            // Recreate the data String.            byte[] retData = theData.getData();            String foundData = new String(retData);            System.out.println("For key: '" + aKey + "' found data: '"                    + foundData + "'.");        }    }    /**     * 查询所有，可遍历数据     * selectAll(Here describes this method function with a few words)        *      * TODO(Here describes this method to be suitable the condition - to be possible to elect)     *       *      * void     */    public static void selectAll() {        Cursor cursor = null;        cursor=bdb.openCursor(null, null);        DatabaseEntry theKey=null;        DatabaseEntry theData=null;             theKey = new DatabaseEntry();        theData = new DatabaseEntry();        while (cursor.getNext(theKey, theData, LockMode.DEFAULT) == OperationStatus.SUCCESS) {            System.out.println(new String(theData.getData()));        }        cursor.close();    }    /**     *  删除方法     * delete(Here describes this method function with a few words)        *      * TODO(Here describes this method to be suitable the condition - to be possible to elect)     *      * @param key      *      * void     */    public static void delete(String key) {        DatabaseEntry keyEntry =null;        try {            keyEntry = new DatabaseEntry(key.getBytes("utf-8"));        } catch (Exception e) {            e.printStackTrace();        }        bdb.delete(null, keyEntry);    }}