Question

这是我的代码我想读取文件milkinfo并在SQLite表中插入带有不同变量的数据。但是这行存在错误

public void main(String[] args) throws IOException {

错误是

Multiple markers at this line
- void is an invalid type for the variable main
- Syntax error on token "(", ; expected
- Syntax error, insert ";" to complete 
 LocalVariableDeclarationStatement

感谢您的支持：）

package com.super;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import android.support.v7.app.ActionBarActivity;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.TextView;

public class Userlevel1 extends ActionBarActivity {
        // Тук се прави Таблицата!!!

    public class MyDatabaseHelper extends SQLiteOpenHelper {

        private static final String DATABASE_NAME = "lactoscan";
        private static final int DATABASE_VERSION = 2;

        // Database creation sql statement
        private static final String DATABASE_CREATE = "CREATE TABLE milklog ( date integer," +
                " time integer primary key, " +
                "deliver integer, " +
                "litres integer," +
                "lsn integer," +
                "calibr integer," +
                "temp integer," +
                "fat integer," +
                "snf integer," +
                "dencity integer," +
                "lac integer," +
                "soli integer," +
                "prot integer);";

        public MyDatabaseHelper(Context context) {
            super(context, DATABASE_NAME, null, DATABASE_VERSION);
        }

        // Method is called during creation of the database
        // Това, трябва да се махне във финалната версия, за да се запазят данните!!!
        @Override
        public void onCreate(SQLiteDatabase database) {
            database.execSQL(DATABASE_CREATE);
        }

        // Method is called during an upgrade of the database,
        @Override
        public void onUpgrade(SQLiteDatabase database,int oldVersion,int newVersion){
            Log.w(MyDatabaseHelper.class.getName(),
                             "Upgrading database from version " + oldVersion + " to "
                             + newVersion + ", which will destroy all old data");



            database.execSQL("DROP TABLE IF EXISTS milklog");
            onCreate(database);
        }


        private MyDatabaseHelper dbHelper;  

        private SQLiteDatabase database;  

        public final static String EMP_TABLE="MyEmployees"; // name of table 

        public final static String EMP_ID="_id"; // id value for employee
        public final static String EMP_NAME="name";  // name of employee
        /** 
         * 
         * @param context 
         */  
        public void MyDB(Context context){  
            dbHelper = new MyDatabaseHelper(context);  
            database = dbHelper.getWritableDatabase();  
        }





        public long createRecords(String id, String name){     
        public void main(String[] args) throws IOException {
            File file = new File("/storage/emulated/0/Download/milkinfo.txt");


            BufferedReader br = new BufferedReader(new InputStreamReader(new FileInputStream(file)));
            String line = null;
            while( (line = br.readLine())!= null ){
                    // \\s+ means any number of whitespaces between tokens
                String [] tokens = line.split("\\s+");
                String fdate = tokens[0];
                String ftime = tokens[1];
                String fdelivern = tokens[2];
                String flitres = tokens[3];
                String flsn = tokens[4];
                String fcalibr = tokens[5];
                String ftemp = tokens[6];
                String ffat = tokens[7];
                String fsnf = tokens[8];
                String fdencity = tokens[9];
                String flac = tokens[10];
                String fsoli = tokens[11];
                String fprot = tokens[12];
            }
            }



           ContentValues values = new ContentValues();  
           values.put(EMP_ID, fdate);  
           values.put(EMP_NAME, name);  
           return database.insert(EMP_TABLE, null, values);  
        }    

        public Cursor selectRecords() {
           String[] cols = new String[] {EMP_ID, EMP_NAME};  
           Cursor mCursor = database.query(true, EMP_TABLE,cols,null  
                    , null, null, null, null, null);  
           if (mCursor != null) {  
             mCursor.moveToFirst();  
           }  
           return mCursor; // iterate to get each value.
        }


    }






    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_userlevel1);


    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.userlevel1, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();
        if (id == R.id.action_settings) {
            return true;
        }
        return super.onOptionsItemSelected(item);
    }
}

Answer 1

除非你的问题中有拼写错误，否则main应该被声明为静态方法。所以试试这个：

public static void main(String[] args) throws IOException {

android在sqlite表中从文本文件中插入多个数据

1 个答案: