关于JDBC下使用SQLite DB问题总结（Windows下和Linux下使用）

e98l66m494

关于JDBC下使用SQLite DB问题总结

   因为公司的服务器在Linux下，同时也需要在Windows下运行，所以这方面的工作必须做的仔细。以下几点收获可以给大伙分享，避免因为一些低级错误影响项目开发。

   在Windows下SQLite JDBC 路径必须是小写，并且路径中需要添加/

   在Linux下SQLite JBDC路径严格区分大小写，并且路径中不需要添加/

   所以在使用过程一定要注意：以下几行代码就是判断这个环境的：

public synchronized List getPetternList(String pattern) throws Exception{
log.info("getPetternList DB="+pattern);
String path = MLotteryContext.getInstance().get("pettern.dir");
File pathDir = new File(path);
if(!pathDir.exists())
pathDir.mkdirs();
log.info("pathDir = "+pathDir);
String petternPath = path+"pattern.db";
File newFile = new File(petternPath);
log.info("==========start delete Old Pettern DB==========");
deleteFile(newFile);
log.info("==========End   delete Old Pettern DB==========");
log.info("======Start =======Write Pettern DB===============");
//------------------------
//if (!newFile.exists()) {
//newFile.createNewFile();
//}
//log.info("=============setExecutable===============");
//newFile.setExecutable(true);
//log.info("=============setReadable=================");
//newFile.setReadable(true);
//log.info("=============setWritable=================");
//newFile.setWritable(true);
//InputStream inStream = new FileInputStream(pattern);
//FileOutputStream fs = new FileOutputStream(newFile);
//byte[] buffer = new byte[1444];
//int bytesum = 0;
//int byteread = 0;
//while ((byteread = inStream.read(buffer)) != -1) {
//bytesum += byteread;
//log.info("=============bytesum===="+bytesum);
////System.out.println(bytesum);
//fs.write(buffer, 0, byteread);
//}
//inStream.close();
//log.info("======End  =======Write Pettern DB===============");
File oldFile = new File(pattern);
boolean bool = oldFile.renameTo(newFile);
log.info("Current PetternDB:"+newFile.getPath()+" bool = " + bool);
Class.forName("org.sqlite.JDBC");
log.info("DB="+petternPath);
log.info("====Start get Server System Type ==========");
Properties props=System.getProperties(); //获得系统属性集
String osName = props.getProperty("os.name"); //操作系统名称
log.info("Current OS Type :"+osName);
log.info("====End  get Server System Type ==========");
osName = osName.toLowerCase();
int index = 0;
index = osName.indexOf("windows");
String JDBC = "jdbc:sqlite:"+petternPath;
if(index > -1){
petternPath = petternPath.toLowerCase();
JDBC="jdbc:sqlite:/"+petternPath;
}
log.info("path = "+petternPath);
log.info("JDBC: "+JDBC);
Connection conn = DriverManager.getConnection(JDBC);
log.info("getPetternList conn="+conn.toString());
Statement stat = conn.createStatement();
ResultSet rs = stat.executeQuery("select * from pattern");
List<String> list = null;
if(rs != null){
list = new ArrayList<String>();
}
while (rs.next()) {
String pid = rs.getString("pattern_id");
log.info("pattern_id = "+pid);
list.add(pid);
}
rs.close();
conn.close();
deleteFile(newFile);
return list;
}只有这样做才能避免老是出现：

java.sql.SQLException: out of memory

at org.sqlite.DB.throwex(DB.java:252)

at org.sqlite.NestedDB.open(NestedDB.java:47)

at org.sqlite.Conn.<init>(Conn.java:36)

at org.sqlite.JDBC.connect(JDBC.java:38)

at java.sql.DriverManager.getConnection(DriverManager.java:582)

这种无厘头的异常！！！！！