X-Git-Url: https://git.m6w6.name/?a=blobdiff_plain;f=libmemcached%2Fmemcached.hpp;h=a83902622495994ed6beab230309023cd9678a2f;hb=4effcb18b27e2d84a8b29bc311b5edbee3c004b6;hp=ecb474aa0fc117372e4cd1a9537a9dc1c1346742;hpb=e072f345a0df02cd6f437e9965debeb6afacb366;p=awesomized%2Flibmemcached

diff --git a/libmemcached/memcached.hpp b/libmemcached/memcached.hpp
index ecb474aa..a8390262 100644
--- a/libmemcached/memcached.hpp
+++ b/libmemcached/memcached.hpp
@@ -16,9 +16,11 @@
 #define LIBMEMCACHEDPP_H
 
 #include <libmemcached/memcached.h>
+#include <libmemcached/exception.hpp>
 
 #include <string.h>
 
+#include <sstream>
 #include <string>
 #include <vector>
 #include <map>
@@ -34,16 +36,46 @@ class Memcache
 {
 public:
 
-  Memcache() 
-    : 
+  Memcache()
+    :
+      servers_list(),
+      memc(),
+      result()
+  {
+    memcached_create(&memc);
+  }
+
+  Memcache(const std::string &in_servers_list)
+    :
+      servers_list(in_servers_list),
       memc(),
       result()
   {
     memcached_create(&memc);
+    init();
   }
 
-  Memcache(memcached_st *clone) 
-    : 
+  Memcache(const std::string &hostname,
+           in_port_t port)
+    :
+      servers_list(),
+      memc(),
+      result()
+  {
+    memcached_create(&memc);
+
+    servers_list.append(hostname);
+    servers_list.append(":");
+    std::ostringstream strsmt;
+    strsmt << port;
+    servers_list.append(strsmt.str());
+
+    init();
+  }
+
+  Memcache(memcached_st *clone)
+    :
+      servers_list(),
       memc(),
       result()
   {
@@ -52,10 +84,23 @@ public:
 
   Memcache(const Memcache &rhs)
     :
+      servers_list(rhs.servers_list),
       memc(),
       result()
   {
     memcached_clone(&memc, const_cast<memcached_st *>(&rhs.getImpl()));
+    init();
+  }
+
+  Memcache &operator=(const Memcache &rhs)
+  {
+    if (this != &rhs)
+    {
+      memcached_clone(&memc, const_cast<memcached_st *>(&rhs.getImpl()));
+      init();
+    }
+
+    return *this;
   }
 
   ~Memcache()
@@ -63,6 +108,14 @@ public:
     memcached_free(&memc);
   }
 
+  void init()
+  {
+    memcached_server_st *servers;
+    servers= memcached_servers_parse(servers_list.c_str());
+    memcached_server_push(&memc, servers);
+    memcached_server_free(servers);
+  }
+
   /**
    * Get the internal memcached_st *
    */
@@ -82,45 +135,141 @@ public:
   /**
    * Return an error string for the given return structure.
    *
-   * @param[in] rc a memcached_return structure
+   * @param[in] rc a memcached_return_t structure
    * @return error string corresponding to given return code in the library.
    */
-  const std::string getError(memcached_return rc) const
+  const std::string getError(memcached_return_t rc) const
   {
     /* first parameter to strerror is unused */
     return memcached_strerror(NULL, rc);
   }
 
-  bool fetch(std::string &key, 
-             std::vector<char> &ret_val,
-             uint32_t *flags,
-             memcached_return *rc)
+
+  bool setBehavior(memcached_behavior_t flag, uint64_t data)
+  {
+    memcached_return_t rc;
+    rc= memcached_behavior_set(&memc, flag, data);
+    return (rc == MEMCACHED_SUCCESS);
+  }
+
+  uint64_t getBehavior(memcached_behavior_t flag) {
+    return memcached_behavior_get(&memc, flag);
+  }
+
+  /**
+   * Return the string which contains the list of memcached servers being
+   * used.
+   *
+   * @return a std::string containing the list of memcached servers
+   */
+  const std::string getServersList() const
+  {
+    return servers_list;
+  }
+
+  /**
+   * Set the list of memcached servers to use.
+   *
+   * @param[in] in_servers_list list of servers
+   * @return true on success; false otherwise
+   */
+  bool setServers(const std::string &in_servers_list)
+  {
+    servers_list.assign(in_servers_list);
+    init();
+
+    return (memcached_server_count(&memc));
+  }
+
+  /**
+   * Add a server to the list of memcached servers to use.
+   *
+   * @param[in] server_name name of the server to add
+   * @param[in] port port number of server to add
+   * @return true on success; false otherwise
+   */
+  bool addServer(const std::string &server_name, in_port_t port)
+  {
+    memcached_return_t rc;
+
+    rc= memcached_server_add(&memc, server_name.c_str(), port);
+
+    return (rc == MEMCACHED_SUCCESS);
+  }
+
+  /**
+   * Remove a server from the list of memcached servers to use.
+   *
+   * @param[in] server_name name of the server to remove
+   * @param[in] port port number of server to remove
+   * @return true on success; false otherwise
+   */
+  bool removeServer(const std::string &server_name, in_port_t port)
+  {
+    std::string tmp_str;
+    std::ostringstream strstm;
+    tmp_str.append(",");
+    tmp_str.append(server_name);
+    tmp_str.append(":");
+    strstm << port;
+    tmp_str.append(strstm.str());
+
+    //memcached_return_t rc= memcached_server_remove(server);
+    
+    return false;
+  }
+
+  /**
+   * Fetches an individual value from the server. mget() must always
+   * be called before using this method.
+   *
+   * @param[in] key key of object to fetch
+   * @param[out] ret_val store returned object in this vector
+   * @return a memcached return structure
+   */
+  memcached_return_t fetch(std::string &key,
+                         std::vector<char> &ret_val)
   {
     char ret_key[MEMCACHED_MAX_KEY];
     size_t value_length= 0;
     size_t key_length= 0;
+    memcached_return_t rc;
+    uint32_t flags= 0;
     char *value= memcached_fetch(&memc, ret_key, &key_length,
-                                 &value_length, flags, rc);
+                                 &value_length, &flags, &rc);
     if (value && ret_val.empty())
     {
       ret_val.reserve(value_length);
       ret_val.assign(value, value + value_length);
       key.assign(ret_key);
-      return true;
+      free(value);
     }
-    return false;
+    else if (value)
+    {
+      free(value);
+    }
+
+    return rc;
   }
 
-  std::vector<char> &get(const std::string &key, 
-                         std::vector<char> &ret_val)
+  /**
+   * Fetches an individual value from the server.
+   *
+   * @param[in] key key of object whose value to get
+   * @param[out] ret_val object that is retrieved is stored in
+   *                     this vector
+   * @return true on success; false otherwise
+   */
+  bool get(const std::string &key,
+           std::vector<char> &ret_val) throw (Error)
   {
     uint32_t flags= 0;
-    memcached_return rc;
+    memcached_return_t rc;
     size_t value_length= 0;
 
     if (key.empty())
     {
-      return ret_val;
+      throw(Error("the key supplied is empty!", false));
     }
     char *value= memcached_get(&memc, key.c_str(), key.length(),
                                &value_length, &flags, &rc);
@@ -128,34 +277,57 @@ public:
     {
       ret_val.reserve(value_length);
       ret_val.assign(value, value + value_length);
+      free(value);
+      return true;
     }
-    return ret_val;
+    return false;
   }
 
-  std::vector<char> &getByKey(const std::string &master_key, 
-                              const std::string &key, 
-                              std::vector<char> &ret_val)
+  /**
+   * Fetches an individual from a server which is specified by
+   * the master_key parameter that is used for determining which
+   * server an object was stored in if key partitioning was
+   * used for storage.
+   *
+   * @param[in] master_key key that specifies server object is stored on
+   * @param[in] key key of object whose value to get
+   * @param[out] ret_val object that is retrieved is stored in
+   *                     this vector
+   * @return true on success; false otherwise
+   */
+  bool getByKey(const std::string &master_key,
+                const std::string &key,
+                std::vector<char> &ret_val) throw(Error)
   {
     uint32_t flags= 0;
-    memcached_return rc;
+    memcached_return_t rc;
     size_t value_length= 0;
 
     if (master_key.empty() || key.empty())
     {
-      return ret_val;
+      throw(Error("the master key or key supplied is empty!", false));
     }
-    char *value= memcached_get_by_key(&memc, 
-                                      master_key.c_str(), master_key.length(), 
+    char *value= memcached_get_by_key(&memc,
+                                      master_key.c_str(), master_key.length(),
                                       key.c_str(), key.length(),
                                       &value_length, &flags, &rc);
     if (value)
     {
       ret_val.reserve(value_length);
       ret_val.assign(value, value + value_length);
+      free(value);
+      return true;
     }
-    return ret_val;
+    return false;
   }
 
+  /**
+   * Selects multiple keys at once. This method always
+   * works asynchronously.
+   *
+   * @param[in] keys vector of keys to select
+   * @return true if all keys are found
+   */
   bool mget(std::vector<std::string> &keys)
   {
     std::vector<const char *> real_keys;
@@ -179,12 +351,12 @@ public:
     }
 
     /*
-     * If the std::vector of keys is empty then we cannot 
+     * If the std::vector of keys is empty then we cannot
      * call memcached_mget as we will get undefined behavior.
      */
     if (! real_keys.empty())
     {
-      memcached_return rc= memcached_mget(&memc, &real_keys[0], &key_len[0], 
+      memcached_return_t rc= memcached_mget(&memc, &real_keys[0], &key_len[0],
                                           real_keys.size());
       return (rc == MEMCACHED_SUCCESS);
     }
@@ -192,30 +364,83 @@ public:
     return false;
   }
 
-  bool set(const std::string &key, 
+  /**
+   * Writes an object to the server. If the object already exists, it will
+   * overwrite the existing object. This method always returns true
+   * when using non-blocking mode unless a network error occurs.
+   *
+   * @param[in] key key of object to write to server
+   * @param[in] value value of object to write to server
+   * @param[in] expiration time to keep the object stored in the server for
+   * @param[in] flags flags to store with the object
+   * @return true on succcess; false otherwise
+   */
+  bool set(const std::string &key,
            const std::vector<char> &value,
            time_t expiration,
-           uint32_t flags)
+           uint32_t flags) throw(Error)
   {
     if (key.empty() || value.empty())
     {
-      return false;
+      throw(Error("the key or value supplied is empty!", false));
     }
-    memcached_return rc= memcached_set(&memc, 
+    memcached_return_t rc= memcached_set(&memc,
                                        key.c_str(), key.length(),
                                        &value[0], value.size(),
                                        expiration, flags);
     return (rc == MEMCACHED_SUCCESS || rc == MEMCACHED_BUFFERED);
   }
 
+  /**
+   * Writes an object to a server specified by the master_key parameter.
+   * If the object already exists, it will overwrite the existing object.
+   *
+   * @param[in] master_key key that specifies server to write to
+   * @param[in] key key of object to write to server
+   * @param[in] value value of object to write to server
+   * @param[in] expiration time to keep the object stored in the server for
+   * @param[in] flags flags to store with the object
+   * @return true on succcess; false otherwise
+   */
+  bool setByKey(const std::string &master_key,
+                const std::string &key,
+                const std::vector<char> &value,
+                time_t expiration,
+                uint32_t flags) throw(Error)
+  {
+    if (master_key.empty() ||
+        key.empty() ||
+        value.empty())
+    {
+      throw(Error("the key or value supplied is empty!", false));
+    }
+    memcached_return_t rc= memcached_set_by_key(&memc, master_key.c_str(),
+                                              master_key.length(),
+                                              key.c_str(), key.length(),
+                                              &value[0], value.size(),
+                                              expiration,
+                                              flags);
+    return (rc == MEMCACHED_SUCCESS);
+  }
+
+  /**
+   * Writes a list of objects to the server. Objects are specified by
+   * 2 vectors - 1 vector of keys and 1 vector of values.
+   *
+   * @param[in] keys vector of keys of objects to write to server
+   * @param[in] values vector of values of objects to write to server
+   * @param[in] expiration time to keep the objects stored in server for
+   * @param[in] flags flags to store with the objects
+   * @return true on success; false otherwise
+   */
   bool setAll(std::vector<std::string> &keys,
               std::vector< std::vector<char> *> &values,
               time_t expiration,
-              uint32_t flags)
+              uint32_t flags) throw(Error)
   {
     if (keys.size() != values.size())
     {
-      return false;
+      throw(Error("The number of keys and values do not match!", false));
     }
     bool retval= true;
     std::vector<std::string>::iterator key_it= keys.begin();
@@ -233,13 +458,22 @@ public:
     return retval;
   }
 
-  bool setAll(std::map<const std::string, std::vector<char> > key_value_map,
+  /**
+   * Writes a list of objects to the server. Objects are specified by
+   * a map of keys to values.
+   *
+   * @param[in] key_value_map map of keys and values to store in server
+   * @param[in] expiration time to keep the objects stored in server for
+   * @param[in] flags flags to store with the objects
+   * @return true on success; false otherwise
+   */
+  bool setAll(std::map<const std::string, std::vector<char> > &key_value_map,
               time_t expiration,
-              uint32_t flags)
+              uint32_t flags) throw(Error)
   {
     if (key_value_map.empty())
     {
-      return false;
+      throw(Error("The key/values are not properly set!", false));
     }
     bool retval= true;
     std::map<const std::string, std::vector<char> >::iterator it=
@@ -249,266 +483,437 @@ public:
       retval= set(it->first, it->second, expiration, flags);
       if (retval == false)
       {
-        return false;
+        std::string err_buff("There was an error setting the key ");
+        err_buff.append(it->first);
+        throw(Error(err_buff, false));
       }
       ++it;
     }
     return true;
   }
 
-  bool setByKey(const std::string &master_key, 
-                const std::string &key, 
-                const std::vector<char> &value,
-                time_t expiration,
-                uint32_t flags)
-  {
-    if (master_key.empty() ||
-        key.empty() ||
-        value.empty())
-    {
-      return false;
-    }
-    memcached_return rc= memcached_set_by_key(&memc, master_key.c_str(), 
-                                              master_key.length(),
-                                              key.c_str(), key.length(),
-                                              &value[0], value.size(),
-                                              expiration,
-                                              flags);
-    return (rc == MEMCACHED_SUCCESS);
-  }
-
-  bool increment(const std::string &key, unsigned int offset, uint64_t *value)
+  /**
+   * Increment the value of the object associated with the specified
+   * key by the offset given. The resulting value is saved in the value
+   * parameter.
+   *
+   * @param[in] key key of object in server whose value to increment
+   * @param[in] offset amount to increment object's value by
+   * @param[out] value store the result of the increment here
+   * @return true on success; false otherwise
+   */
+  bool increment(const std::string &key, uint32_t offset, uint64_t *value) throw(Error)
   {
     if (key.empty())
     {
-      return false;
+      throw(Error("the key supplied is empty!", false));
     }
-    memcached_return rc= memcached_increment(&memc, key.c_str(), key.length(),
+    memcached_return_t rc= memcached_increment(&memc, key.c_str(), key.length(),
                                              offset, value);
     return (rc == MEMCACHED_SUCCESS);
   }
 
-  bool decrement(const std::string &key, unsigned int offset, uint64_t *value)
+  /**
+   * Decrement the value of the object associated with the specified
+   * key by the offset given. The resulting value is saved in the value
+   * parameter.
+   *
+   * @param[in] key key of object in server whose value to decrement
+   * @param[in] offset amount to increment object's value by
+   * @param[out] value store the result of the decrement here
+   * @return true on success; false otherwise
+   */
+  bool decrement(const std::string &key, uint32_t offset, uint64_t *value)
+    throw(Error)
   {
     if (key.empty())
     {
-      return false;
+      throw(Error("the key supplied is empty!", false));
     }
-    memcached_return rc= memcached_decrement(&memc, key.c_str(), 
+    memcached_return_t rc= memcached_decrement(&memc, key.c_str(),
                                              key.length(),
                                              offset, value);
     return (rc == MEMCACHED_SUCCESS);
   }
 
 
+  /**
+   * Add an object with the specified key and value to the server. This
+   * function returns false if the object already exists on the server.
+   *
+   * @param[in] key key of object to add
+   * @param[in] value of object to add
+   * @return true on success; false otherwise
+   */
   bool add(const std::string &key, const std::vector<char> &value)
+    throw(Error)
   {
     if (key.empty() || value.empty())
     {
-      return false;
+      throw(Error("the key or value supplied is empty!", false));
     }
-    memcached_return rc= memcached_add(&memc, key.c_str(), key.length(), 
+    memcached_return_t rc= memcached_add(&memc, key.c_str(), key.length(),
                                        &value[0], value.size(), 0, 0);
     return (rc == MEMCACHED_SUCCESS);
   }
 
-  bool addByKey(const std::string &master_key, 
-                const std::string &key, 
-                const std::vector<char> &value)
+  /**
+   * Add an object with the specified key and value to the server. This
+   * function returns false if the object already exists on the server. The
+   * server to add the object to is specified by the master_key parameter.
+   *
+   * @param[in[ master_key key of server to add object to
+   * @param[in] key key of object to add
+   * @param[in] value of object to add
+   * @return true on success; false otherwise
+   */
+  bool addByKey(const std::string &master_key,
+                const std::string &key,
+                const std::vector<char> &value) throw(Error)
   {
     if (master_key.empty() ||
-        key.empty() || 
+        key.empty() ||
         value.empty())
     {
-      return false;
+      throw(Error("the master key or key supplied is empty!", false));
     }
-    memcached_return rc= memcached_add_by_key(&memc, 
+    memcached_return_t rc= memcached_add_by_key(&memc,
                                               master_key.c_str(),
                                               master_key.length(),
                                               key.c_str(),
                                               key.length(),
-                                              &value[0], 
+                                              &value[0],
                                               value.size(),
                                               0, 0);
     return (rc == MEMCACHED_SUCCESS);
   }
 
-  bool replace(const std::string &key, const std::vector<char> &value)
+  /**
+   * Replaces an object on the server. This method only succeeds
+   * if the object is already present on the server.
+   *
+   * @param[in] key key of object to replace
+   * @param[in[ value value to replace object with
+   * @return true on success; false otherwise
+   */
+  bool replace(const std::string &key, const std::vector<char> &value) throw(Error)
   {
     if (key.empty() ||
         value.empty())
     {
-      return false;
+      throw(Error("the key or value supplied is empty!", false));
     }
-    memcached_return rc= memcached_replace(&memc, key.c_str(), key.length(),
+    memcached_return_t rc= memcached_replace(&memc, key.c_str(), key.length(),
                                            &value[0], value.size(),
                                            0, 0);
     return (rc == MEMCACHED_SUCCESS);
   }
 
-  bool replaceByKey(const std::string &master_key, 
-                    const std::string &key, 
+  /**
+   * Replaces an object on the server. This method only succeeds
+   * if the object is already present on the server. The server
+   * to replace the object on is specified by the master_key param.
+   *
+   * @param[in] master_key key of server to replace object on
+   * @param[in] key key of object to replace
+   * @param[in[ value value to replace object with
+   * @return true on success; false otherwise
+   */
+  bool replaceByKey(const std::string &master_key,
+                    const std::string &key,
                     const std::vector<char> &value)
   {
     if (master_key.empty() ||
         key.empty() ||
         value.empty())
     {
-      return false;
+      throw(Error("the master key or key supplied is empty!", false));
     }
-    memcached_return rc= memcached_replace_by_key(&memc, 
-                                                  master_key.c_str(), 
+    memcached_return_t rc= memcached_replace_by_key(&memc,
+                                                  master_key.c_str(),
                                                   master_key.length(),
-                                                  key.c_str(), 
+                                                  key.c_str(),
                                                   key.length(),
-                                                  &value[0], 
-                                                  value.size(), 
+                                                  &value[0],
+                                                  value.size(),
                                                   0, 0);
     return (rc == MEMCACHED_SUCCESS);
   }
 
+  /**
+   * Places a segment of data before the last piece of data stored.
+   *
+   * @param[in] key key of object whose value we will prepend data to
+   * @param[in] value data to prepend to object's value
+   * @return true on success; false otherwise
+   */
   bool prepend(const std::string &key, const std::vector<char> &value)
+    throw(Error)
   {
     if (key.empty() || value.empty())
     {
-      return false;
+      throw(Error("the key or value supplied is empty!", false));
     }
-    memcached_return rc= memcached_prepend(&memc, key.c_str(), key.length(),
+    memcached_return_t rc= memcached_prepend(&memc, key.c_str(), key.length(),
                                            &value[0], value.size(), 0, 0);
     return (rc == MEMCACHED_SUCCESS);
   }
 
-  bool prependByKey(const std::string &master_key, 
-                    const std::string &key, 
+  /**
+   * Places a segment of data before the last piece of data stored. The
+   * server on which the object where we will be prepending data is stored
+   * on is specified by the master_key parameter.
+   *
+   * @param[in] master_key key of server where object is stored
+   * @param[in] key key of object whose value we will prepend data to
+   * @param[in] value data to prepend to object's value
+   * @return true on success; false otherwise
+   */
+  bool prependByKey(const std::string &master_key,
+                    const std::string &key,
                     const std::vector<char> &value)
+      throw(Error)
   {
     if (master_key.empty() ||
         key.empty() ||
         value.empty())
     {
-      return false;
+      throw(Error("the master key or key supplied is empty!", false));
     }
-    memcached_return rc= memcached_prepend_by_key(&memc, 
-                                                  master_key.c_str(), 
+    memcached_return_t rc= memcached_prepend_by_key(&memc,
+                                                  master_key.c_str(),
                                                   master_key.length(),
-                                                  key.c_str(), 
+                                                  key.c_str(),
                                                   key.length(),
-                                                  &value[0], 
+                                                  &value[0],
                                                   value.size(),
                                                   0,
                                                   0);
     return (rc == MEMCACHED_SUCCESS);
   }
 
+  /**
+   * Places a segment of data at the end of the last piece of data stored.
+   *
+   * @param[in] key key of object whose value we will append data to
+   * @param[in] value data to append to object's value
+   * @return true on success; false otherwise
+   */
   bool append(const std::string &key, const std::vector<char> &value)
+    throw(Error)
   {
     if (key.empty() || value.empty())
     {
-      return false;
+      throw(Error("the key or value supplied is empty!", false));
     }
-    memcached_return rc= memcached_append(&memc, 
-                                          key.c_str(), 
+    memcached_return_t rc= memcached_append(&memc,
+                                          key.c_str(),
                                           key.length(),
-                                          &value[0], 
-                                          value.size(), 
+                                          &value[0],
+                                          value.size(),
                                           0, 0);
     return (rc == MEMCACHED_SUCCESS);
   }
 
-  bool appendByKey(const std::string &master_key, 
-                   const std::string &key, 
+  /**
+   * Places a segment of data at the end of the last piece of data stored. The
+   * server on which the object where we will be appending data is stored
+   * on is specified by the master_key parameter.
+   *
+   * @param[in] master_key key of server where object is stored
+   * @param[in] key key of object whose value we will append data to
+   * @param[in] value data to append to object's value
+   * @return true on success; false otherwise
+   */
+  bool appendByKey(const std::string &master_key,
+                   const std::string &key,
                    const std::vector<char> &value)
+    throw(Error)
   {
     if (master_key.empty() ||
         key.empty() ||
         value.empty())
     {
-      return false;
+      throw(Error("the master key or key supplied is empty!", false));
     }
-    memcached_return rc= memcached_append_by_key(&memc,
-                                                 master_key.c_str(), 
+    memcached_return_t rc= memcached_append_by_key(&memc,
+                                                 master_key.c_str(),
                                                  master_key.length(),
-                                                 key.c_str(), 
+                                                 key.c_str(),
                                                  key.length(),
-                                                 &value[0], 
-                                                 value.size(), 
+                                                 &value[0],
+                                                 value.size(),
                                                  0, 0);
     return (rc == MEMCACHED_SUCCESS);
   }
 
-  bool cas(const std::string &key, 
-           const std::vector<char> &value, 
-           uint64_t cas_arg)
+  /**
+   * Overwrite data in the server as long as the cas_arg value
+   * is still the same in the server.
+   *
+   * @param[in] key key of object in server
+   * @param[in] value value to store for object in server
+   * @param[in] cas_arg "cas" value
+   */
+  bool cas(const std::string &key,
+           const std::vector<char> &value,
+           uint64_t cas_arg) throw(Error)
   {
     if (key.empty() || value.empty())
     {
-      return false;
+      throw(Error("the key or value supplied is empty!", false));
     }
-    memcached_return rc= memcached_cas(&memc, key.c_str(), key.length(),
-                                       &value[0], value.size(), 
+    memcached_return_t rc= memcached_cas(&memc, key.c_str(), key.length(),
+                                       &value[0], value.size(),
                                        0, 0, cas_arg);
     return (rc == MEMCACHED_SUCCESS);
   }
 
-  bool casByKey(const std::string &master_key, 
-                const std::string &key, 
-                const std::vector<char> &value, 
-                uint64_t cas_arg)
+  /**
+   * Overwrite data in the server as long as the cas_arg value
+   * is still the same in the server. The server to use is
+   * specified by the master_key parameter.
+   *
+   * @param[in] master_key specifies server to operate on
+   * @param[in] key key of object in server
+   * @param[in] value value to store for object in server
+   * @param[in] cas_arg "cas" value
+   */
+  bool casByKey(const std::string &master_key,
+                const std::string &key,
+                const std::vector<char> &value,
+                uint64_t cas_arg) throw(Error)
   {
     if (master_key.empty() ||
         key.empty() ||
         value.empty())
     {
-      return false;
+      throw(Error("the master key, key or value supplied is empty!", false));
     }
-    memcached_return rc= memcached_cas_by_key(&memc,
-                                              master_key.c_str(), 
+    memcached_return_t rc= memcached_cas_by_key(&memc,
+                                              master_key.c_str(),
                                               master_key.length(),
-                                              key.c_str(), 
+                                              key.c_str(),
                                               key.length(),
-                                              &value[0], 
+                                              &value[0],
                                               value.size(),
                                               0, 0, cas_arg);
     return (rc == MEMCACHED_SUCCESS);
   }
 
-  bool remove(const std::string &key)
+  /**
+   * Delete an object from the server specified by the key given.
+   *
+   * @param[in] key key of object to delete
+   * @return true on success; false otherwise
+   */
+  bool remove(const std::string &key) throw(Error)
   {
     if (key.empty())
     {
-      return false;
+      throw(Error("the key supplied is empty!", false));
     }
-    memcached_return rc= memcached_delete(&memc, key.c_str(), key.length(), 0);
+    memcached_return_t rc= memcached_delete(&memc, key.c_str(), key.length(), 0);
     return (rc == MEMCACHED_SUCCESS);
   }
 
-  bool removeByKey(const std::string &master_key, 
-                   const std::string &key)
+  /**
+   * Delete an object from the server specified by the key given.
+   *
+   * @param[in] key key of object to delete
+   * @param[in] expiration time to delete the object after
+   * @return true on success; false otherwise
+   */
+  bool remove(const std::string &key,
+              time_t expiration) throw(Error)
+  {
+    if (key.empty())
+    {
+      throw(Error("the key supplied is empty!", false));
+    }
+    memcached_return_t rc= memcached_delete(&memc,
+                                          key.c_str(),
+                                          key.length(),
+                                          expiration);
+    return (rc == MEMCACHED_SUCCESS);
+  }
+
+  /**
+   * Delete an object from the server specified by the key given.
+   *
+   * @param[in] master_key specifies server to remove object from
+   * @param[in] key key of object to delete
+   * @return true on success; false otherwise
+   */
+  bool removeByKey(const std::string &master_key,
+                   const std::string &key) throw(Error)
   {
     if (master_key.empty() || key.empty())
     {
-      return false;
+      throw(Error("the master key or key supplied is empty!", false));
     }
-    memcached_return rc= memcached_delete_by_key(&memc, 
-                                                 master_key.c_str(), 
+    memcached_return_t rc= memcached_delete_by_key(&memc,
+                                                 master_key.c_str(),
                                                  master_key.length(),
-                                                 key.c_str(), 
-                                                 key.length(), 
+                                                 key.c_str(),
+                                                 key.length(),
                                                  0);
     return (rc == MEMCACHED_SUCCESS);
   }
 
+  /**
+   * Delete an object from the server specified by the key given.
+   *
+   * @param[in] master_key specifies server to remove object from
+   * @param[in] key key of object to delete
+   * @param[in] expiration time to delete the object after
+   * @return true on success; false otherwise
+   */
+  bool removeByKey(const std::string &master_key,
+                   const std::string &key,
+                   time_t expiration) throw(Error)
+  {
+    if (master_key.empty() || key.empty())
+    {
+      throw(Error("the master key or key supplied is empty!", false));
+    }
+    memcached_return_t rc= memcached_delete_by_key(&memc,
+                                                 master_key.c_str(),
+                                                 master_key.length(),
+                                                 key.c_str(),
+                                                 key.length(),
+                                                 expiration);
+    return (rc == MEMCACHED_SUCCESS);
+  }
+
+  /**
+   * Wipe the contents of memcached servers.
+   *
+   * @param[in] expiration time to wait until wiping contents of
+   *                       memcached servers
+   * @return true on success; false otherwise
+   */
   bool flush(time_t expiration)
   {
-    memcached_return rc= memcached_flush(&memc, expiration);
+    memcached_return_t rc= memcached_flush(&memc, expiration);
     return (rc == MEMCACHED_SUCCESS);
   }
 
-  bool fetchExecute(memcached_execute_function *callback,
+  /**
+   * Callback function for result sets. It passes the result
+   * sets to the list of functions provided.
+   *
+   * @param[in] callback list of callback functions
+   * @param[in] context pointer to memory reference that is
+   *                    supplied to the calling function
+   * @param[in] num_of_callbacks number of callback functions
+   * @return true on success; false otherwise
+   */
+  bool fetchExecute(memcached_execute_fn *callback,
                     void *context,
-                    unsigned int num_of_callbacks)
+                    uint32_t num_of_callbacks)
   {
-    memcached_return rc= memcached_fetch_execute(&memc,
+    memcached_return_t rc= memcached_fetch_execute(&memc,
                                                  callback,
                                                  context,
                                                  num_of_callbacks);
@@ -526,8 +931,65 @@ public:
     return version;
   }
 
+  /**
+   * Retrieve memcached statistics. Populate a std::map with the retrieved
+   * stats. Each server will map to another std::map of the key:value stats.
+   *
+   * @param[out] stats_map a std::map to be populated with the memcached
+   *                       stats
+   * @return true on success; false otherwise
+   */
+  bool getStats(std::map< std::string, std::map<std::string, std::string> >
+                &stats_map)
+  {
+    memcached_return_t rc;
+    memcached_stat_st *stats= memcached_stat(&memc, NULL, &rc);
+
+    if (rc != MEMCACHED_SUCCESS &&
+        rc != MEMCACHED_SOME_ERRORS)
+    {
+      return false;
+    }
+
+    uint32_t server_count= memcached_server_count(&memc);
+
+    /*
+     * For each memcached server, construct a std::map for its stats and add
+     * it to the std::map of overall stats.
+     */
+    for (uint32_t x= 0; x < server_count; x++)
+    {
+      memcached_server_instance_st instance=
+        memcached_server_instance_by_position(&memc, x);
+      std::ostringstream strstm;
+      std::string server_name(memcached_server_name(instance));
+      server_name.append(":");
+      strstm << memcached_server_port(instance);
+      server_name.append(strstm.str());
+
+      std::map<std::string, std::string> server_stats;
+      char **list= NULL;
+      char **ptr= NULL;
+
+      list= memcached_stat_get_keys(&memc, &stats[x], &rc);
+      for (ptr= list; *ptr; ptr++)
+      {
+        char *value= memcached_stat_get_value(&memc, &stats[x], *ptr, &rc);
+        server_stats[*ptr]= value;
+        free(value);
+      }
+     
+      stats_map[server_name]= server_stats;
+      free(list);
+    }
+
+    memcached_stat_free(&memc, stats);
+    return true;
+  }
+
 private:
 
+  std::string servers_list;
   memcached_st memc;
   memcached_result_st result;
 };