Question

I am trying to read a file containing 158000 records(12MB) separted by newline and put that record in the mysql database but after inserting around 49000 records my java program throws following exception

Exception in thread "main" java.lang.OutOfMemoryError: Java heap space
    at java.util.jar.Manifest$FastInputStream.<init>(Manifest.java:315)
    at java.util.jar.Manifest$FastInputStream.<init>(Manifest.java:310)
    at java.util.jar.Manifest.read(Manifest.java:178)
    at java.util.jar.Manifest.<init>(Manifest.java:52)
    at java.util.jar.JarFile.getManifestFromReference(JarFile.java:167)
    at java.util.jar.JarFile.getManifest(JarFile.java:148)
    at sun.misc.URLClassPath$JarLoader$2.getManifest(URLClassPath.java:696) at sun.misc.URLClassPath$JarLoader$2.getManifest(URLClassPath.java:696)

    at java.net.URLClassLoader.defineClass(URLClassLoader.java:228)
    at java.net.URLClassLoader.access$000(URLClassLoader.java:58)
    at java.net.URLClassLoader$1.run(URLClassLoader.java:197)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
    at com.mysql.jdbc.Util.handleNewInstance(Util.java:430) at com.mysql.jdbc.Util.handleNewInstance(Util.java:430)

    at com.mysql.jdbc.PreparedStatement.getInstance(PreparedStatement.java:553)
    at com.mysql.jdbc.ConnectionImpl.clientPrepareStatement(ConnectionImpl.java:1378)
    at com.mysql.jdbc.ConnectionImpl.prepareStatement(ConnectionImpl.java:4143)
    at com.mysql.jdbc.ConnectionImpl.prepareStatement(ConnectionImpl.java:4042)
    at loadcsvdatabase.LoadCsvDatabase.fnLoadCsvIntoMemory(LoadCsvDatabase.java:52)
    at loadcsvdatabase.LoadCsvDatabase.main(LoadCsvDatabase.java:29)

Java 插入数据

FileInputStream file;
        DataInputStream dataIn;
        BufferedReader bReader;
        Connection conn= openConnection();
        String strRecord=new String();
        String[]strSplittedRecord;
        file= new FileInputStream("D:\Java\CountryWhois.txt");
        dataIn= new DataInputStream(file);
        bReader= new BufferedReader(new InputStreamReader(dataIn));
        PreparedStatement insertStmt;
        String strQuery="insert into countrywhois values(?,?,?,?,?,?)";
        while((strRecord=bReader.readLine())!=null)
        {

            strSplittedRecord=strRecord.split(",");

         try {

             insertStmt=conn.prepareStatement(strQuery);
             insertStmt.setString(1,strSplittedRecord[0].substring(1, strSplittedRecord[0].length()-1));
             insertStmt.setString(2,strSplittedRecord[1].substring(1, strSplittedRecord[1].length()-1));
             insertStmt.setString(3,strSplittedRecord[2].substring(1, strSplittedRecord[2].length()-1));
             insertStmt.setString(4,strSplittedRecord[3].substring(1, strSplittedRecord[3].length()-1));
             insertStmt.setString(5,strSplittedRecord[4].substring(1, strSplittedRecord[4].length()-1));
             insertStmt.setString(6,strSplittedRecord[5].substring(1, strSplittedRecord[5].length()-1));
             int nResultInsert=insertStmt.executeUpdate();
             if(nResultInsert!=0)
             {
                System.out.println("Inserted 1");


             }
             else
             {
                if(conn!=null)
                {
                    conn.close();
                    System.out.println("Disconnected from database");
                }
             }
         }
         catch (Exception e) 
         {
             conn.close();
             e.printStackTrace(System.out);        
         }

        }

电话:insertStmt=conn.prepareStatement (strQuery);

Please suggest me why my program is running out of memory exception..

Answer 1

你们每次都制作新写明的纪录片。这并不是应该如何使用编写声明。而且,你永远不会关闭已经建立的签字国,这可能造成外部观察,但这并不是根本问题。

你们必须只创造一种准备的声明和再利用。然后,在插入所有记录后,关闭了发言稿和链接。

Answer 2

insertStmt=conn.prepareStatement(strQuery);

应在<代码>之外填写。确切地说,它是在《<代码>>>>上签字的。

Answer 3

您应修订您的法典,以便:

...

try {
  Connection conn = openConnection();
  try {

    String strQuery="insert into countrywhois values(?,?,?,?,?,?)";
    PreparedStatement insertStmt=conn.prepareStatement(strQuery);
    while (...) {
        try {
            ....
            int nResultInsert=insertStmt.executeUpdate();

            // handle your result here (e.g. print/log)
            // DO NOT close() here, continue with loop

        } catch (Exception e) {
            // handle your exception here (e.g. print/log)
            // DO NOT close() here, continue with loop, OR break loop
        }
    }

  } finally {
      // closing SQL Connection no matter what happens to your while-loop
      conn.close();
  }
} catch (Exception e) {
    // handle your exception here (e.g. print/log)
}

友情链接