RocksDB存储在默认列族

墨蓝 2021-12-23 03:41 200阅读 0赞

使用RocksDB需要导入如下maven：

<dependency>
                <groupId>org.rocksdb</groupId>
                <artifactId>rocksdbjni</artifactId>
                <version>5.9.2</version>
            </dependency>

程序示例：

import org.rocksdb.Options;
    import org.rocksdb.RocksDB;
    import org.rocksdb.RocksDBException;
    import org.rocksdb.RocksIterator;
    
    public class TestRocksdb {
    
        //参数数据库存储位置
        public TestRocksdb(String dbPath){
            rocksDB=createRocksDB(dbPath);
        }
    
        //RocksDB引用
        public static RocksDB rocksDB;
        //加载RocksDB引擎
        static{
            RocksDB.loadLibrary();
        }
    
        public static RocksDB createRocksDB(String dbPath){
            try {
                //RocksDB初始化设置
                Options options=new Options();
                //如果本地文件失踪则创建
                options.setCreateIfMissing(true);
                //创建RocksDB对象
                rocksDB=RocksDB.open(options,dbPath);
                return rocksDB;
            } catch (RocksDBException e) {
                e.printStackTrace();
                return null;
            }
        }
    
    
    
        public boolean put(byte[] key,byte[] value ){
            try {
                rocksDB.put(key,value);
                return true;
            } catch (RocksDBException e) {
                e.printStackTrace();
                return  false;
            }
        }
    
    
        public byte[] get(byte[] key){
            try {
                byte[] value=rocksDB.get(key);
                return value;
            } catch (RocksDBException e) {
                e.printStackTrace();
                return null;
            }
        }
    
    
        public void showAllData(){
            RocksIterator iter = rocksDB.newIterator();
            for(iter.seekToFirst(); iter.isValid(); iter.next()) {
                byte[] key=iter.key();
                byte[] value=iter.value();
                System.out.println("key="+new String(key)+" --> value="+new String(value));
            }
        }
    
        public static void main(String[] args) {
            TestRocksdb rocksdb=new TestRocksdb("/test");
            //要存放的数据key=key1,value="hello world"
            boolean flag=rocksdb.put("key1".getBytes(),"hello world".getBytes());
            if(flag==true){
                System.out.println("存储成功");
            }else{
                System.out.println("存储失败");
            }
            //从数据库中获取数据
            byte[] bytes=rocksdb.get("key1".getBytes());
            System.out.println(new String(bytes));
        }
    }

结果：

![20190625175814704.jpg][]

[20190625175814704.jpg]: /images/20211223/d6260c1813a34f0d84009d63b30899de.png