rocksdb/tools/shell/ShellState.h
Dhruba Borthakur 2b443ba887 Titile: a command line shell to read/write data from a leveldb thrift server
Summary: implemented a commond line shell to talk with leveldb thrift server, which is based on state pattern and can be easily extended.

Test Plan: build and run

Reviewers: dhruba, zshao, heyongqiang

Differential Revision: https://reviews.facebook.net/D4713
2012-08-23 09:41:05 -07:00

88 lines
1.8 KiB
C++

#ifndef TOOLS_SHELL_SHELLSTATE
#define TOOLS_SHELL_SHELLSTATE
class ShellContext;
/*
* Currently, there are four types of state in total
* 1. start state: the first state the program enters
* 2. connecting state: the program try to connnect to a leveldb server, whose
* previous states could be "start" or "connected" states
* 3. connected states: the program has already connected to a server, and is
* processing user commands
* 4. stop state: the last state the program enters, do some cleanning up things
*/
class ShellState {
public:
virtual void run(ShellContext *) = 0;
virtual ~ShellState() {}
};
class ShellStateStart : public ShellState {
public:
static ShellStateStart * getInstance(void) {
static ShellStateStart instance;
return &instance;
}
virtual void run(ShellContext *);
private:
ShellStateStart() {}
virtual ~ShellStateStart() {}
};
class ShellStateStop : public ShellState {
public:
static ShellStateStop * getInstance(void) {
static ShellStateStop instance;
return &instance;
}
virtual void run(ShellContext *);
private:
ShellStateStop() {}
virtual ~ShellStateStop() {}
};
class ShellStateConnecting : public ShellState {
public:
static ShellStateConnecting * getInstance(void) {
static ShellStateConnecting instance;
return &instance;
}
virtual void run(ShellContext *);
private:
ShellStateConnecting() {}
virtual ~ShellStateConnecting() {}
};
class ShellStateConnected : public ShellState {
public:
static ShellStateConnected * getInstance(void) {
static ShellStateConnected instance;
return &instance;
}
virtual void run(ShellContext *);
private:
ShellStateConnected() {}
virtual ~ShellStateConnected() {}
void unknownCmd();
void handleConError(ShellContext *);
void helpMsg();
};
#endif