四、BDB JE学习(对java中内置对象的存储)

 对不同类型的数据处理

DatabaseEntry来绑定基本的JAVA数据类型，主要有String、Character、Boolean、Byte、Short、Integer、Long、Float、Double.

还是要在你的D盘中创建bdb文件夹。

例子:

 

package test; 
import java.io.File; 
import java.io.UnsupportedEncodingException; 
import com.sleepycat.bind.EntityBinding; 
import com.sleepycat.bind.EntryBinding; 
import com.sleepycat.bind.tuple.LongBinding; 
import com.sleepycat.bind.tuple.TupleBinding; 
import com.sleepycat.je.Database; 
import com.sleepycat.je.DatabaseConfig; 
import com.sleepycat.je.DatabaseEntry; 
import com.sleepycat.je.DatabaseException; 
import com.sleepycat.je.Environment; 
import com.sleepycat.je.EnvironmentConfig; 
import com.sleepycat.je.EnvironmentLockedException; 
import com.sleepycat.je.LockMode; 
import com.sleepycat.je.OperationStatus; 
/** 
 * 对java中的内置对象的存储 
 * @author Administrator 
 * 
 */ 
public class MyTest { 
 public static void main(String[] args) { 
  Environment env=null; 
  Database db = null; 
  EnvironmentConfig envconfig=new EnvironmentConfig(); 
  envconfig.setAllowCreate(true); 
  try { 
   env=new Environment(new File("D://bdb"),envconfig); 
   DatabaseConfig dbconfig=new DatabaseConfig(); 
   dbconfig.setAllowCreate(true); 
   db=env.openDatabase(null, "dbac.db", dbconfig); 
   String key="mykey"; 
   DatabaseEntry thekey=new DatabaseEntry(); 
   thekey.setData(key.getBytes("utf-8")); 
    
   Long value=new Long(123456); 
   DatabaseEntry thevalue=new DatabaseEntry(); 
   EntryBinding myBinging=TupleBinding.getPrimitiveBinding(Long.class); 
   myBinging.objectToEntry(value, thevalue); 
   //LongBinding myLongBinging=(LongBinding)TupleBinding.getPrimitiveBinding(Long.class); 
   //myLongBinging.objectToEntry(value, thevalue); 
   db.put(null, thekey, thevalue); 
   DatabaseEntry valueEntry = new DatabaseEntry(); 
   OperationStatus status= db.get(null, thekey, valueEntry, LockMode.DEFAULT); 
   if(status==OperationStatus.SUCCESS){ 
    //Long number=myLongBinging.entryToObject(valueEntry); 
    Long number=(Long) myBinging.entryToObject(valueEntry); 
    System.out.println(env.getDatabaseNames()); 
    System.out.println(number); 
   } 
  } catch (EnvironmentLockedException e) { 
   e.printStackTrace(); 
  } catch (Exception e) { 
   e.printStackTrace(); 
  } finally{ 
   if(db!=null){ 
    try { 
     db.close(); 
    } catch (DatabaseException e) { 
     e.printStackTrace(); 
    } 
   } 
   if(env!=null){ 
    try { 
     env.cleanLog(); 
     env.close(); 
    } catch (DatabaseException e) { 
     e.printStackTrace(); 
    } 
   } 
  } 
 } 
}