#include <iostream>

//using namespace std;

#include <stdio.h>
#include "libpq-fe.h"
#include <string>
#include <cstdio>
#include <stdlib.h>

int     main() {
    PGconn          *conn;
    PGresult        *res;
    int             rec_count;
    int             row;
    int             col;
    FILE            *stream;

    conn = PQconnectdb("hostaddr=192.168.143.93 port=5432 connect_timeout=10 dbname=NexentaSearch user=postgres password=postgres");
    if (PQstatus(conn) == CONNECTION_BAD) {
        fprintf(stderr, "Connection to database failed: %sn",PQerrorMessage(conn));
     puts("No connection");
        exit(0);
    }

    res = PQexec(conn, "select path from tasks order by id");

    if (PQresultStatus(res) != PGRES_TUPLES_OK) {
        printf("We didn't get the data");
        exit(0);
    }

    rec_count = PQntuples(res);

Connection con = DriverManager.getConnection(url, user, pass);
ArrayList<String> arrayString = new ArrayList<String>();
String query = "тут запрос";

ResultSet res = con.createStatement.executeQuery(query);

while (res.next) {
    arrayString.add(res.getString("1"))
}