Hi, need to create a cache

[ShaveDave27]

Hi,
I'm trying to create a cache which will use direct mapping and output a miss rate for a list of integers.
I'm struggling quite a bit.
I think I have created the cache OK, probably not though - heres the code.

 import java.util.*; 
import java.util.LinkedHashMap;
 
public class Cache<A,B>
{
public int Size; 
public LinkedHashMap<A,B> Direct;
 
 
 
public Cache(int Size)
{
this.Size = Size;
this.CacheCapacity = CacheCapacity;
this.blocks = blocks;
Direct = new LinkedHashMap<A,B>(Size);
 
}
public B get(A index)
{
return Direct.get(index);
}
public void enter(A index, B Tag)
{
Direct.put(index, Tag);
}
public Collection<Map.Entry<A,B>> getAll() 
{
return new ArrayList<Map.Entry<A,B>>(Direct.entrySet());
}
 
 
 
}
 

I have to have another class, which i call memory, with the test data in.
My cache should be 0.25KB and each block should have 8 bytes.
It's quite confusing really!
Any help would be very appreciated

Thanks

Dave

[r035198x]

Hi,
I'm trying to create a cache which will use direct mapping and output a miss rate for a list of integers.
I'm struggling quite a bit.
I think I have created the cache OK, probably not though - heres the code.

import java.util.*;
import java.util.Linke dHashMap;

public class Cache<A,B>
{
public int Size;
public LinkedHashMap<A ,B> Direct;



public Cache(int Size)
{
this.Size = Size;
this.CacheCapac ity = CacheCapacity;
this.blocks = blocks;
Direct = new LinkedHashMap<A ,B>(Size);

}
public B get(A index)
{
return Direct.get(inde x);
}
public void enter(A index, B Tag)
{
Direct.put(inde x, Tag);
}
public Collection<Map. Entry<A,B>> getAll()
{
return new ArrayList<Map.E ntry<A,B>>(Dire ct.entrySet());
}



}

I have to have another class, which i call memory, with the test data in.
My cache should be 0.25KB and each block should have 8 bytes.
It's quite confusing really!
Any help would be very appreciated

Thanks

Dave

1.) when posting code, please use code tags.
2.) That won't compile. Please try to make it compile first then you can tell us what the problem is.

[ShaveDave27]

1.) when posting code, please use code tags.
2.) That won't compile. Please try to make it compile first then you can tell us what the problem is.

Sorry,
heres the code that compiles:

import java.util.*;
import java.util.LinkedHashMap;
 
public class Cache<A,B>
{
    public int Size;   
    public LinkedHashMap<A,B> Direct;
 
 
 
    public Cache(int Size)
    {
        this.Size = Size;
 
        Direct = new LinkedHashMap<A,B>(Size);
 
    }
    public B get(A index)
    {
        return Direct.get(index);
    }
    public void enter(A index, B Tag)
    {
        Direct.put(index, Tag);
    }
    public Collection<Map.Entry<A,B>> getAll() 
    {
    return new ArrayList<Map.Entry<A,B>>(Direct.entrySet());
     }
 
 
 
}
 

1) This cache is meant to be able to calculate a miss rate when test data is entered. I can work out the miss rate, but when I input data I can't figure out how to make the cache tell if it's a hit or miss.
2) I need to make the index hold more than one piece of data, at the moment, when a new piece of data is entered, it just replaces the old data.

Thanks

Dave

[r035198x]

Sorry,
heres the code that compiles:

import java.util.*;
import java.util.LinkedHashMap;
 
public class Cache<A,B>
{
public int Size; 
public LinkedHashMap<A,B> Direct;
 
 
 
public Cache(int Size)
{
this.Size = Size;
 
Direct = new LinkedHashMap<A,B>(Size);
 
}
public B get(A index)
{
return Direct.get(index);
}
public void enter(A index, B Tag)
{
Direct.put(index, Tag);
}
public Collection<Map.Entry<A,B>> getAll() 
{
return new ArrayList<Map.Entry<A,B>>(Direct.entrySet());
}
 
 
 
}
 

1) This cache is meant to be able to calculate a miss rate when test data is entered. I can work out the miss rate, but when I input data I can't figure out how to make the cache tell if it's a hit or miss.
2) I need to make the index hold more than one piece of data, at the moment, when a new piece of data is entered, it just replaces the old data.

Thanks

Dave

Perhaps if you explain what you want to do with an example ...

[ShaveDave27]

Perhaps if you explain what you want to do with an example ...

OK,

I have some test data, for example some integers, 22, 33, 22.


These get converted into binary code and then get stored in the cache.
22 = 10110
33=100001
22 = 10110

These binary codes get seperated into an index and a tag. The index is the first two numbers (for all 3 integers this is 10) Then the rest of the code is the tag.

When i input 22, 33, 22 i input it as the index and the tag.
for example I would input 22 as "10" "110".
Then 110 will be stored in index 10.
But when i input 33(also stored in index 10) it will replace 22.
I want them both to be in the index.
And when i input 22 again I want it to realise the same tag has been entered and output "hit", as a variable which can increase everytime there is a hit.

Hope you understand this better

Thanks

Dave

[r035198x]

OK,

I have some test data, for example some integers, 22, 33, 22.


These get converted into binary code and then get stored in the cache.
22 = 10110
33=100001
22 = 10110

These binary codes get seperated into an index and a tag. The index is the first two numbers (for all 3 integers this is 10) Then the rest of the code is the tag.

When i input 22, 33, 22 i input it as the index and the tag.
for example I would input 22 as "10" "110".
Then 110 will be stored in index 10.
But when i input 33(also stored in index 10) it will replace 22.
I want them both to be in the index.
And when i input 22 again I want it to realise the same tag has been entered and output "hit", as a variable which can increase everytime there is a hit.

Hope you understand this better

Thanks

Dave

Therefore you need the structure

HashMap<Binary, ArrayList<Binar y>> or ofcourse you could simply do away with creating a Binary number class and use
HashMap<String, ArrayList<Strin g>>

Do you see how you can use it?

[mufumbo]

Hey,
why don't you use EHCACHE? It's awesome and have all the features that you need, so you don't have to re-invent the wheel.

ehcache.sf.net

Cheers
Rafael