在jOOQ中动态创建条件

如何解决在jOOQ中动态创建条件

我有以下两条jOOQ行，效果很好：

    Formulas f = FORMULAS.as("f");
    Condition condition = x > y ? f.SK.eq(sk) : f.SK.eq(0);

现在，由于我有100个需要相同条件的表，并且条件比上面的示例复杂得多，因此我想创建一个类似这样的方法：

public Condition getCondition(Table table,int x,int y,int sk) {
        Condition condition = // write here a generic condition
        return condition;
}

但是我不知道如何一般性地将列分配给表。该如何处理？

解决方法

您可以使用以下内容：

#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <netinet/in.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <signal.h>
#include <stdlib.h>
#define MAXSIZE 256
int isTerminated(char buffer[],int len);
void writeSocket(int sock,char buffer[]);

int main(){
    struct sockaddr_in Local;
    struct sockaddr_in Client;
    short int port=1745;

    char buffer[MAXSIZE];
    int sockfd,newsockfd,n,nread,nwrite,len;
    int turn_off=0;//Controllare le impostazioni del contatore

    sockfd=socket(AF_INET,SOCK_STREAM,0);
    if(sockfd<0){
        fprintf(stderr,"Server: Socket creating failed!\n");
        return -1;
    }else
        printf("Server: Socket created!\n");
    memset(&Local,sizeof(Local));
    Local.sin_family=AF_INET;
    Local.sin_addr.s_addr=htonl(INADDR_ANY);
    Local.sin_port=htons(port);
    
    if(bind(sockfd,(struct sockaddr*)&Local,sizeof(Local))<0){
        fprintf(stderr,"Server: Binding socket failed!\n");
        return -1;
    }else
        printf("Server: Bind ok!\n");

    if(listen(sockfd,10)<0){
        fprintf(stderr,"Server: Listen failed!\n");
        return -1;
    }else
        printf("Server: Listen ok!\n");

    while(1){
        buffer[0]='\0';
        printf("Server: Waiting for connection...\n");
        newsockfd=accept(sockfd,(struct sockaddr*)&Client,&len);
        printf("Server: Connection accepted!\n");


        nread=0;
        while((n=read(newsockfd,&(buffer[nread]),MAXSIZE))>0){
            nread+=n;
            printf("Server: Ho letto %d caratteri con %d totali!\n",nread);
            if(isTerminated(buffer,nread))//Fine stringa
                break;
        }
        buffer[nread]='\0';


        printf("Ho ricevuto il messaggio %s\n",buffer);
        if(!strcmp(buffer,"Turn OFF")){
            buffer[0]='\0';
            strcpy(buffer,"Counter OFF");
            turn_off=1;
        }else{
            buffer[0]='\0';
            strcpy(buffer,"OK");
        }

        /*nwrite=0;
        buffer[strlen(buffer)]='\0';
        int str_len=strlen(buffer)+1;
        while((str_len>nwrite) && (n=write(newsockfd,&(buffer[nwrite]),str_len-nwrite)>0))
            nwrite+=n;*/
        writeSocket(sockfd,buffer);

        close(newsockfd);
        if(turn_off)//Spegni il contatore e salva la sessione
            break;
    }
    close(sockfd);

    return 0;
}

void writeSocket(int sock,char buffer[]){
    buffer[strlen(buffer)]='\0';
    int str_len=strlen(buffer)+1;
    int nwrite=0;
    int n;
    printf("Devo inviare il messaggio: %s\n",buffer);
    printf("Valore n: %d\n",sock);
    while((str_len>nwrite) && (n=write(sock,str_len-nwrite)>0))
        nwrite+=n;
    
}

int isTerminated(char buffer[],int len){
    int i;
    for(i=0; i<=len; i++)
        if(buffer[i] == '\0')
            return 1;
    return 0;
}

或更详细，但输入安全版本：

public static Condition makeCondition(Table<?> table,int x,int y,int sk) {
    Field<Integer> skField = table.field("sk",int.class);
    return x > y ? skField.eq(sk) : skField.eq(0);
}