MacFormat 1995 January/macformat-020.iso/Shareware City/Developers/ACL/CCL Folder/Examples/c.connections/Connections.cp

Text File | 1994-08-31 | 4.3 KB | 217 lines | [TEXT/MMCC]

/********************************************
 **** Core Class Demo by Yves Schmid
 ****
 **** Connections.cp
 ****
 **** Author:        Yves Schmid
 **** Created:      14 August 1994
 **** Modified:     14 August 1994
 **** Version:      1.0
 **** Compatible:   C++
 ****
 **** Description:  Connections and duplication demo
 ****
 *************************/


#include "CoreHead.h"

#include <stdio.h>
#include <string.h>

//*************************************


const long cmd_printmyself    = 1024;    // A command which asks the stringnode to print its string


//*************************************
// A simple CoreHead which stocks and prints a string

class stringnode : public CoreHead
{
    char    data[256];


    protected:

    // Override the "receivecmd" to handle the "cmd_printmyself" command:
    void receivecmd(long cmd, void *info);

    public:

    inline char *getstring(void) {return data;}

    // Constructors

    stringnode(char *str, CoreHead *supervisor);    // Object with a supervisor
    stringnode(char *str =NULL);                    // Unlinked object

    // Destructor

    ~stringnode();

    // Duplication system:
    Core *duplicate(void);
    void copyfrom(Core *);
};

//..............................

stringnode::stringnode(char *str, CoreHead *supervisor) : CoreHead(supervisor,0,1)
                                            // Initialize CoreHead with the supervisor,
                                            // destination entry 0 and 1 entry in the new
                                            // created object

{
    newlevel();            // A new heritage level!
    strcpy(data,str);    // Copy string
}

//..............................


stringnode::stringnode(char *str) : CoreHead(1)    // Unlinked object with one entry
{
    newlevel();                    // A new heritage level!

    if (str) strcpy(data,str);    // Copy string
    else str[0] = 0;            // else empty string
}

//..............................

stringnode::~stringnode()
{
    printf("%s deleted\n", data);
}

//..............................


void stringnode::receivecmd(long cmd, void *info)
{
    switch(cmd)
    {
        case cmd_printmyself:    // Ok it is the right message, I can print the string.
        printf("%s\n",data);
        break;

        default:                // Unknow message? Call the parent class
        CoreHead::receivecmd(cmd,info);
    }
}

//..............................

Core *stringnode::duplicate(void)
{
    stringnode *no;

    clearerror();

    no = new stringnode();

    if (no)
    {
        no->copyfrom(this);
        importerror(no);
    }
    else adderror(CERR_NOMEMORY);

    return no;
}

void stringnode::copyfrom(Core *core)
{

    CoreHead::copyfrom(core);

    if (core->getlevel()>=getlevel())
    {
        strcpy(data,((stringnode*)core)->getstring());
        strcat(data,"-2");
    }
}

//..............................


//*******************************************************************


void main()
{
    // Creating a tree:
    //
    //          A
    //        /   \
    //       B1     B2
    //      / \    / \
    //     C1 C2 D1  D2

    printf("*** CCL Tree demo ***\n\n");
    printf("Creating a tree:\n\n");
    printf("         A            \n");
    printf("       /   \\        \n");
    printf("      B1    B2        \n");
    printf("     /\\     /\\    \n");
    printf("    C1 C2  D1 D2    \n");

    //*****************************

    stringnode *a,*b1,*b2,*c1,*c2,*d1,*d2,*tree2;

    a = new stringnode("A");
    b1 = new stringnode("B1",a);
    b2 = new stringnode("B2",a);
    c1 = new stringnode("C1",b1);
    c2 = new stringnode("C2",b1);
    d1 = new stringnode("D1",b2);
    d2 = new stringnode("D2",b2);

    //*****************************

    printf("\n\n* Duplicate \"B1\", result is a new tree:\n");
    printf("      B1-2       \n");
    printf("     /       \\   \n");
    printf("    C1-2  C2-2  \n");

    tree2 = (stringnode*)b1->duplicate();
    tree2->remove();    // Removes new tree from its supervisor which is "A"

    printf("\n\n* Scan the new tree:\n");
    tree2->docmd(cmd_printmyself,CCF_EVERYWHERE);


    //*****************************

    printf("\n\n* Connect the root of the second tree to \"B2\", new structure is:\n");
    printf("         A            \n");
    printf("       /   \\        \n");
    printf("      B1    B2<----------B1-2       \n");
    printf("     /\\     /\\          /  \\        \n");
    printf("    C1 C2  D1 D2       C1-2  C2-2    \n");


    tree2->connectto(b2);

    printf("\n\n* Scan the full structure using the root of the second tree (B1-2):\n");
    tree2->docmd(cmd_printmyself,CCF_EVERYWHERE);


    //*****************************


    printf("\n\n* Delete the \"B1\" node:\n");
    delete b1;

    printf("\n\n* Delete the \"A\" node:\n");
    delete a;

    printf("\n\n* Delete the second tree:\n");
    delete tree2;
}