Thread: Cannot find symbol ERROR

Working on a bin sort; user enters a bunch of number and then I sort them.

I keep getting the error "cannot find symbol" and an arrow pointing to the period in mbin.elementAt(i) and ever time I have an arrayList command in my method. What's going on, can the method not access the arrayList created in the main? Help.

//CS 108
 
import java.util.*;
public class HW4
{
 
public static ArrayList<String> mbin = new ArrayList<String>();
public static ArrayList[] sbins = new ArrayList[10];
 
public static void main(String args[])
{
 
    for (int i=0; i<=9; i++)     //create each of the sort bins, 0 through 9
    {
    sbins[i] = new ArrayList();
    }
 
	Scanner input = new Scanner(System.in);
	String numIn = null;
 
	System.out.println("Input a value from 0 to 9999. When done inputting hit the ENTER key alone.");
 
	while((numIn = input.nextLine( )).length( ) > 0)
	{
		if(numIn.length( ) > 4)
		{
		System.out.println("The number you entered is too big. Input a value from 0 to 9999.");
		}
		else
		{
		System.out.println("Input a value from 0 to 9999 if done inputting hit the ENTER key alone.");
		mbin.add(numIn);
		}
	}
 
	System.out.print("You entered: ");
	System.out.println( mbin.toString() );
 
	MtoS(3);
	StoM();
	MtoS(2);
	StoM();
	MtoS(1);
	StoM();
	MtoS(0);
	StoM();
 
	System.out.println( mbin.toString() );
}
 
public static void MtoS(int p)
{
	for(int i = 0; i < (mbin.size() - 1); i++)
	{
		String s = mbin.elementAt(i);
		char c = ' ';
 
		if(s.length( ) == 4)
		{
		c = s.charAt(p);
		}
		else if(s.length( ) == 3)
		{
		c = s.charAt(p-1);
		}
		else if(s.length( ) == 2)
		{
		c = s.charAt(p-2);
		}
		else
		{
		c = s.charAt(p-3);
		}
 
 
		if(c == '9')
		{
		sbins[9].addElement(s);
		}
		else if(c == '8')
		{
		sbins[8].addElement(s);
		}
		else if(c == '7')
		{
		sbins[7].addElement(s);
		}
		else if(c == '6')
		{
		sbins[6].addElement(s);
		}
		else if(c == '5')
		{
		sbins[5].addElement(s);
		}
		else if(c == '4')
		{
		sbins[4].addElement(s);
		}
		else if(c == '3')
		{
		sbins[3].addElement(s);
		}
		else if(c == '2')
		{
		sbins[2].addElement(s);
		}
		else if(c == '1')
		{
		sbins[1].addElement(s);
		}
		else
		{
		sbins[0].addElement(s);
		}
	}
}
 
public static void StoM()
{
	for(int i = 0; i < (sbins[9].size() - 1); i++)
	{
	String s = sbins[9].elementAt(i);
	mbin.addElement(s);
	}
	for(int i = 0; i < (sbins[8].size() - 1); i++)
	{
	String s = sbins[8].elementAt(i);
	mbin.addElement(s);
	}
	for(int i = 0; i < (sbins[7].size() - 1); i++)
	{
	String s = sbins[7].elementAt(i);
	mbin.addElement(s);
	}
	for(int i = 0; i < (sbins[6].size() - 1); i++)
	{
	String s = sbins[6].elementAt(i);
	mbin.addElement(s);
	}
	for(int i = 0; i < (sbins[5].size() - 1); i++)
	{
	String s = sbins[5].elementAt(i);
	mbin.addElement(s);
	}
	for(int i = 0; i < (sbins[4].size() - 1); i++)
	{
	String s = sbins[4].elementAt(i);
	mbin.addElement(s);
	}
	for(int i = 0; i < (sbins[3].size() - 1); i++)
	{
	String s = sbins[3].elementAt(i);
	mbin.addElement(s);
	}
	for(int i = 0; i < (sbins[2].size() - 1); i++)
	{
	String s = sbins[2].elementAt(i);
	mbin.addElement(s);
	}
	for(int i = 0; i < (sbins[1].size() - 1); i++)
	{
	String s = sbins[1].elementAt(i);
	mbin.addElement(s);
	}
	for(int i = 0; i < (sbins[0].size() - 1); i++)
	{
	String s = sbins[0].elementAt(i);
	mbin.addElement(s);
	}
}
 
 
}

Where am I using arraylist like an array? Also, the error is only occurring in my methods.

@Javapenguin You can have an array of ArrayLists. Tried adding the string generics to it but that doesn't change anything.

Sorry, I assumed you were when I saw
public static ArrayList[] sbins = new ArrayList[10];

Please highlight your code with

[highlight=Java] *Code* [/highlight]

rather than code tags, although code is better than nothing

The reason you are having trouble accessing the variable is because your methods are static, they only use the first variable, to solve this make it non-static (remove the static modifier) and don't call it from the main method. EG

public class someClass
{
  public void someNonStaticMethod()
  {
    //Code eluded
  }
  public someClass()
  {
    //Code here instead of main.
    someNonStaticMethod();
  }
  public static void main(String[] args)
  {
    new someClass();
  }
}

Originally Posted by copeg

See the API for ArrayList.
ArrayList (Java Platform SE 6)
There is no method elementAt, or addElement (you are probably looking for get(int) and add(int))

THANK YOU! I was using vector methods *facepalm*