Files
mongo/examples/java/com/wiredtiger/examples/ex_call_center.java
2015-01-04 14:07:56 -05:00

301 lines
10 KiB
Java

/*-
* Public Domain 2014-2015 MongoDB, Inc.
* Public Domain 2008-2014 WiredTiger, Inc.
*
* This is free and unencumbered software released into the public domain.
*
* Anyone is free to copy, modify, publish, use, compile, sell, or
* distribute this software, either in source code form or as a compiled
* binary, for any purpose, commercial or non-commercial, and by any
* means.
*
* In jurisdictions that recognize copyright laws, the author or authors
* of this software dedicate any and all copyright interest in the
* software to the public domain. We make this dedication for the benefit
* of the public at large and to the detriment of our heirs and
* successors. We intend this dedication to be an overt act of
* relinquishment in perpetuity of all present and future rights to this
* software under copyright law.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
* IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR
* OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*
* ex_call_center.java
* This is an example application that demonstrates how to map a
* moderately complex SQL application into WiredTiger.
*/
package com.wiredtiger.examples;
import com.wiredtiger.db.*;
import java.io.*;
import java.util.*;
/*! [call-center decl] */
/*
* In SQL, the tables are described as follows:
*
* CREATE TABLE Customers(id INTEGER PRIMARY KEY,
* name VARCHAR(30), address VARCHAR(50), phone VARCHAR(15))
* CREATE INDEX CustomersPhone ON Customers(phone)
*
* CREATE TABLE Calls(id INTEGER PRIMARY KEY, call_date DATE,
* cust_id INTEGER, emp_id INTEGER, call_type VARCHAR(12),
* notes VARCHAR(25))
* CREATE INDEX CallsCustDate ON Calls(cust_id, call_date)
*
* In this example, both tables will use record numbers for their IDs, which
* will be the key. The C structs for the records are as follows.
*/
/* Customer records. */
class Customer {
public long id;
public String name;
public String address;
public String phone;
public Customer(long id, String name, String address, String phone) {
this.id = id;
this.name = name;
this.address = address;
this.phone = phone;
}
public Customer() {}
}
/* Call records. */
class Call {
public long id;
public long call_date;
public long cust_id;
public long emp_id;
public String call_type;
public String notes;
public Call(long id, long call_date, long cust_id, long emp_id,
String call_type, String notes) {
this.id = id;
this.call_date = call_date;
this.cust_id = cust_id;
this.emp_id = emp_id;
this.call_type = call_type;
this.notes = notes;
}
public Call() {}
}
/*! [call-center decl] */
public class ex_call_center {
public static String home;
public static int
callCenterExample()
throws WiredTigerException
{
Connection conn;
Cursor cursor;
Session session;
int count, ret;
SearchStatus nearstatus;
List<Customer> custSample = new ArrayList<Customer>();
List<Call> callSample = new ArrayList<Call>();
custSample.add(new Customer(0, "Professor Oak",
"LeafGreen Avenue", "123-456-7890"));
custSample.add(new Customer(0, "Lorelei",
"Sevii Islands", "098-765-4321"));
callSample.add(new Call(0, 32, 1, 2, "billing", "unavailable"));
callSample.add(new Call(0, 33, 1, 2, "billing", "available"));
callSample.add(new Call(0, 34, 1, 2, "reminder", "unavailable"));
callSample.add(new Call(0, 35, 1, 2, "reminder", "available"));
/*
* Create a clean test directory for this run of the test program if the
* environment variable isn't already set (as is done by make check).
*/
if (System.getenv("WIREDTIGER_HOME") == null) {
home = "WT_HOME";
try {
Process proc = Runtime.getRuntime().exec("/bin/rm -rf WT_HOME");
BufferedReader br = new BufferedReader(
new InputStreamReader(proc.getInputStream()));
while(br.ready())
System.out.println(br.readLine());
br.close();
new File("WT_HOME").mkdir();
} catch (IOException ioe) {
System.err.println("IOException: WT_HOME: " + ioe);
return(1);
}
} else
home = null;
try {
conn = wiredtiger.open(home, "create");
session = conn.open_session(null);
} catch (WiredTigerException wte) {
System.err.println("WiredTigerException: " + wte);
return(1);
}
/* Note: further error checking omitted for clarity. */
/*! [call-center work] */
/*
* Create the customers table, give names and types to the columns.
* The columns will be stored in two groups: "main" and "address",
* created below.
*/
ret = session.create("table:customers",
"key_format=r," +
"value_format=SSS," +
"columns=(id,name,address,phone)," +
"colgroups=(main,address)");
/* Create the main column group with value columns except address. */
ret = session.create(
"colgroup:customers:main", "columns=(name,phone)");
/* Create the address column group with just the address. */
ret = session.create(
"colgroup:customers:address", "columns=(address)");
/* Create an index on the customer table by phone number. */
ret = session.create(
"index:customers:phone", "columns=(phone)");
/* Populate the customers table with some data. */
cursor = session.open_cursor("table:customers", null, "append");
for (Customer cust : custSample) {
cursor.putValueString(cust.name);
cursor.putValueString(cust.address);
cursor.putValueString(cust.phone);
ret = cursor.insert();
}
ret = cursor.close();
/*
* Create the calls table, give names and types to the columns. All the
* columns will be stored together, so no column groups are declared.
*/
ret = session.create("table:calls",
"key_format=r," +
"value_format=qrrSS," +
"columns=(id,call_date,cust_id,emp_id,call_type,notes)");
/*
* Create an index on the calls table with a composite key of cust_id
* and call_date.
*/
ret = session.create("index:calls:cust_date",
"columns=(cust_id,call_date)");
/* Populate the calls table with some data. */
cursor = session.open_cursor("table:calls", null, "append");
for (Call call : callSample) {
cursor.putValueLong(call.call_date);
cursor.putValueLong(call.cust_id);
cursor.putValueLong(call.emp_id);
cursor.putValueString(call.call_type);
cursor.putValueString(call.notes);
ret = cursor.insert();
}
ret = cursor.close();
/*
* First query: a call arrives. In SQL:
*
* SELECT id, name FROM Customers WHERE phone=?
*
* Use the cust_phone index, lookup by phone number to fill the
* customer record. The cursor will have a key format of "S" for a
* string because the cust_phone index has a single column ("phone"),
* which is of type "S".
*
* Specify the columns we want: the customer ID and the name. This
* means the cursor's value format will be "rS".
*/
cursor = session.open_cursor(
"index:customers:phone(id,name)", null, null);
cursor.putKeyString("123-456-7890");
ret = cursor.search();
if (ret == 0) {
Customer cust = new Customer();
cust.id = cursor.getValueLong();
cust.name = cursor.getValueString();
System.out.println("Read customer record for " + cust.name +
" (ID " + cust.id + ")");
}
ret = cursor.close();
/*
* Next query: get the recent order history. In SQL:
*
* SELECT * FROM Calls WHERE cust_id=? ORDER BY call_date DESC LIMIT 3
*
* Use the call_cust_date index to find the matching calls. Since it is
* is in increasing order by date for a given customer, we want to start
* with the last record for the customer and work backwards.
*
* Specify a subset of columns to be returned. (Note that if these were
* all covered by the index, the primary would not have to be accessed.)
* Stop after getting 3 records.
*/
cursor = session.open_cursor(
"index:calls:cust_date(cust_id,call_type,notes)",
null, null);
/*
* The keys in the index are (cust_id,call_date) -- we want the largest
* call date for a given cust_id. Search for (cust_id+1,0), then work
* backwards.
*/
long custid = 1;
cursor.putKeyLong(custid + 1);
cursor.putKeyLong(0);
nearstatus = cursor.search_near();
/*
* If the table is empty, search_near will return WT_NOTFOUND, else the
* cursor will be positioned on a matching key if one exists, or an
* adjacent key if one does not. If the positioned key is equal to or
* larger than the search key, go back one.
*/
if (ret == 0 && (nearstatus == SearchStatus.LARGER ||
nearstatus == SearchStatus.FOUND))
ret = cursor.prev();
for (count = 0; ret == 0 && count < 3; ++count) {
Call call = new Call();
call.cust_id = cursor.getValueLong();
call.call_type = cursor.getValueString();
call.notes = cursor.getValueString();
if (call.cust_id != custid)
break;
System.out.println("Call record: customer " + call.cust_id +
" (" + call.call_type +
": " + call.notes + ")");
ret = cursor.prev();
}
/*! [call-center work] */
ret = conn.close(null);
return (ret);
}
public static int
main(String[] argv)
{
try {
return (callCenterExample());
}
catch (WiredTigerException wte) {
System.err.println("Exception: " + wte);
return (-1);
}
}
}