diff --git a/__crypto/simple_contract/Cargo.lock b/__crypto/simple_contract/Cargo.lock
index 0472123..2ae7e01 100644
--- a/__crypto/simple_contract/Cargo.lock
+++ b/__crypto/simple_contract/Cargo.lock
@@ -425,10 +425,11 @@ dependencies = [
 
 [[package]]
 name = "rust_util"
-version = "0.6.25"
+version = "0.6.26"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "26a080a375b53e1a584388ac4c611f55e41629c79b40ed1c630d497b995c8cf8"
+checksum = "3cf5c22991d8fa9a12da6e745e9ea6180df21ed48a8e28431c64fa5a2985d5d9"
 dependencies = [
+ "clap",
  "lazy_static",
  "libc",
  "term",
@@ -528,9 +529,9 @@ checksum = "8ea5119cdb4c55b55d432abb513a0429384878c15dde60cc77b1c99de1a95a6a"
 
 [[package]]
 name = "syn"
-version = "1.0.56"
+version = "1.0.57"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a9802ddde94170d186eeee5005b798d9c159fa970403f1be19976d0cfb939b72"
+checksum = "4211ce9909eb971f111059df92c45640aad50a619cf55cd76476be803c4c68e6"
 dependencies = [
  "proc-macro2",
  "quote",
diff --git a/__crypto/simple_contract/Cargo.toml b/__crypto/simple_contract/Cargo.toml
index 763b7d2..c2c566a 100644
--- a/__crypto/simple_contract/Cargo.toml
+++ b/__crypto/simple_contract/Cargo.toml
@@ -16,5 +16,5 @@ ripemd160 = "0.8.0"
 sha2 = "0.8.1"
 serde = { version = "1.0", features = ["derive"] }
 serde_json = "1.0"
-rust_util = "0.6"
+rust_util = { version = "0.6", features = ["use_clap"] }
 clap = "2.33"
diff --git a/__crypto/simple_contract/src/cmd.rs b/__crypto/simple_contract/src/cmd.rs
deleted file mode 100644
index 3a0da05..0000000
--- a/__crypto/simple_contract/src/cmd.rs
+++ /dev/null
@@ -1,11 +0,0 @@
-use clap::{ArgMatches, App};
-use rust_util::XResult;
-pub type CommandError = XResult<()>;
-
-pub trait Command {
-    fn name(&self) -> &str;
-    
-    fn subcommand<'a>(&self) -> App<'a, 'a>;
-    
-    fn run(&self, arg_matches: &ArgMatches, _: &ArgMatches) -> CommandError;
-}
diff --git a/__crypto/simple_contract/src/cmd_credit_create.rs b/__crypto/simple_contract/src/cmd_credit_create.rs
index 3d7edb6..d5e0a40 100644
--- a/__crypto/simple_contract/src/cmd_credit_create.rs
+++ b/__crypto/simple_contract/src/cmd_credit_create.rs
@@ -1,6 +1,6 @@
 use std::fs;
 use clap::{App, Arg, ArgMatches, SubCommand};
-use crate::cmd::{Command, CommandError};
+use rust_util::util_clap::{Command, CommandError};
 use crate::util::JsonKeyPair;
 use crate::tx::{Transaction, TransactionBody};
 use crate::engine::ContractEngine;
@@ -49,6 +49,6 @@ impl Command for CommandImpl {
         let engine = ContractEngine::new();
         engine.execute(&tx)?;
 
-        Ok(())
+        Ok(None)
     }
 }
diff --git a/__crypto/simple_contract/src/cmd_credit_issue.rs b/__crypto/simple_contract/src/cmd_credit_issue.rs
index d5fdef9..8abc415 100644
--- a/__crypto/simple_contract/src/cmd_credit_issue.rs
+++ b/__crypto/simple_contract/src/cmd_credit_issue.rs
@@ -1,6 +1,6 @@
 use std::fs;
 use clap::{App, Arg, ArgMatches, SubCommand};
-use crate::cmd::{Command, CommandError};
+use rust_util::util_clap::{Command, CommandError};
 use crate::util::JsonKeyPair;
 use crate::tx::{Transaction, TransactionBody};
 use crate::engine::ContractEngine;
@@ -54,6 +54,6 @@ impl Command for CommandImpl {
         let engine = ContractEngine::new();
         engine.execute(&tx)?;
 
-        Ok(())
+        Ok(None)
     }
 }
diff --git a/__crypto/simple_contract/src/cmd_credit_query.rs b/__crypto/simple_contract/src/cmd_credit_query.rs
index 6c69a75..d9efe89 100644
--- a/__crypto/simple_contract/src/cmd_credit_query.rs
+++ b/__crypto/simple_contract/src/cmd_credit_query.rs
@@ -1,6 +1,6 @@
 use std::fs;
 use clap::{App, Arg, ArgMatches, SubCommand};
-use crate::cmd::{Command, CommandError};
+use rust_util::util_clap::{Command, CommandError};
 use crate::util::JsonKeyPair;
 use crate::tx::{Transaction, TransactionBody};
 use crate::engine::ContractEngine;
@@ -49,6 +49,6 @@ impl Command for CommandImpl {
         let engine = ContractEngine::new();
         engine.execute(&tx)?;
 
-        Ok(())
+        Ok(None)
     }
 }
diff --git a/__crypto/simple_contract/src/cmd_credit_queryall.rs b/__crypto/simple_contract/src/cmd_credit_queryall.rs
index 0ae0e78..2440c58 100644
--- a/__crypto/simple_contract/src/cmd_credit_queryall.rs
+++ b/__crypto/simple_contract/src/cmd_credit_queryall.rs
@@ -1,6 +1,6 @@
 use std::fs;
 use clap::{App, Arg, ArgMatches, SubCommand};
-use crate::cmd::{Command, CommandError};
+use rust_util::util_clap::{Command, CommandError};
 use crate::util::JsonKeyPair;
 use crate::tx::{Transaction, TransactionBody};
 use crate::engine::ContractEngine;
@@ -44,6 +44,6 @@ impl Command for CommandImpl {
         let engine = ContractEngine::new();
         engine.execute(&tx)?;
 
-        Ok(())
+        Ok(None)
     }
 }
diff --git a/__crypto/simple_contract/src/cmd_credit_transfer.rs b/__crypto/simple_contract/src/cmd_credit_transfer.rs
index 5194ccc..45e1aaf 100644
--- a/__crypto/simple_contract/src/cmd_credit_transfer.rs
+++ b/__crypto/simple_contract/src/cmd_credit_transfer.rs
@@ -1,6 +1,6 @@
 use std::fs;
 use clap::{App, Arg, ArgMatches, SubCommand};
-use crate::cmd::{Command, CommandError};
+use rust_util::util_clap::{Command, CommandError};
 use crate::util::JsonKeyPair;
 use crate::tx::{Transaction, TransactionBody};
 use crate::engine::ContractEngine;
@@ -54,6 +54,6 @@ impl Command for CommandImpl {
         let engine = ContractEngine::new();
         engine.execute(&tx)?;
 
-        Ok(())
+        Ok(None)
     }
 }
diff --git a/__crypto/simple_contract/src/cmd_default.rs b/__crypto/simple_contract/src/cmd_default.rs
deleted file mode 100644
index 7e8925a..0000000
--- a/__crypto/simple_contract/src/cmd_default.rs
+++ /dev/null
@@ -1,17 +0,0 @@
-use clap::{App, Arg, ArgMatches};
-use crate::cmd::CommandError;
-
-pub struct CommandImpl;
-impl CommandImpl {
-
-    pub fn process_command<'a>(app: App<'a, 'a>) -> App<'a, 'a> {
-        app.arg(Arg::with_name("verbose").long("verbose").short("v").multiple(true).help("Show verbose info"))
-    }
-
-    pub fn run(arg_matches: &ArgMatches) -> CommandError {
-        let verbose_count = arg_matches.occurrences_of("verbose");
-        information!("Verbose count: {}", verbose_count);
-        information!("This is default command cli ...");
-        Ok(())
-    }
-}
\ No newline at end of file
diff --git a/__crypto/simple_contract/src/cmd_genkey.rs b/__crypto/simple_contract/src/cmd_genkey.rs
index 3c947fb..7960e5a 100644
--- a/__crypto/simple_contract/src/cmd_genkey.rs
+++ b/__crypto/simple_contract/src/cmd_genkey.rs
@@ -1,7 +1,7 @@
 use std::fs;
 use std::fs::File;
 use clap::{App, Arg, ArgMatches, SubCommand};
-use crate::cmd::{Command, CommandError};
+use rust_util::util_clap::{Command, CommandError};
 use crate::util::{JsonKeyPair, make_key_pair};
 
 pub struct CommandImpl;
@@ -21,12 +21,12 @@ impl Command for CommandImpl {
         let tag = sub_arg_matches.value_of("tag");
         if let Ok(_) = File::open(output) {
             failure!("Output file exists: {}", output);
-            return Ok(());
+            return Ok(None);
         }
         let (pri_key, pub_key) = make_key_pair();
         let json_key_pair = JsonKeyPair::from(pri_key, pub_key, tag.map(|t| t.into()));
         success!("Write gen key file: {}", output);
         fs::write(output, json_key_pair.to_json()?.as_bytes())?;
-        Ok(())
+        Ok(None)
     }
 }
diff --git a/__crypto/simple_contract/src/main.rs b/__crypto/simple_contract/src/main.rs
index 5572317..c8db560 100644
--- a/__crypto/simple_contract/src/main.rs
+++ b/__crypto/simple_contract/src/main.rs
@@ -7,8 +7,6 @@ mod credit_util;
 mod engine;
 mod engine_plugin_credit;
 
-mod cmd;
-mod cmd_default;
 mod cmd_genkey;
 mod cmd_credit_create;
 mod cmd_credit_issue;
@@ -16,30 +14,32 @@ mod cmd_credit_transfer;
 mod cmd_credit_query;
 mod cmd_credit_queryall;
 
-use clap::App;
-use cmd::{Command, CommandError};
+use clap::{App, Arg, ArgMatches};
+use rust_util::{XResult, util_clap::{CommandError, CommandExecutor, DefaultCommand}};
 
-fn main() -> CommandError {
-    let commands: Vec<Box<dyn Command>> = vec![
-        Box::new(cmd_genkey::CommandImpl),
-        Box::new(cmd_credit_create::CommandImpl),
-        Box::new(cmd_credit_issue::CommandImpl),
-        Box::new(cmd_credit_transfer::CommandImpl),
-        Box::new(cmd_credit_query::CommandImpl),
-        Box::new(cmd_credit_queryall::CommandImpl),
-    ];
-    let mut app = App::new(env!("CARGO_PKG_NAME"))
-                    .version(env!("CARGO_PKG_VERSION"))
-                    .about(env!("CARGO_PKG_DESCRIPTION"));
-    app = cmd_default::CommandImpl::process_command(app);
-    for command in &commands {
-        app = app.subcommand(command.subcommand());
+pub struct DefaultCommandImpl;
+impl DefaultCommand for DefaultCommandImpl {
+    fn process_command<'a>(&self, app: App<'a, 'a>) -> App<'a, 'a> {
+        app.arg(Arg::with_name("verbose").long("verbose").short("v").multiple(true).help("Show verbose info"))
     }
-    let matches = app.get_matches();
-    for command in &commands {
-        if let Some(sub_cmd_matches) = matches.subcommand_matches(command.name()) {
-            return command.run(&matches, sub_cmd_matches);
-        }
+
+    fn run(&self, arg_matches: &ArgMatches) -> CommandError {
+        let verbose_count = arg_matches.occurrences_of("verbose");
+        information!("Verbose count: {}", verbose_count);
+        information!("Try use help (--help) print usage");
+        Ok(None)
     }
-    cmd_default::CommandImpl::run(&matches)
+}
+
+fn main() -> XResult<()> {
+    let mut c = CommandExecutor::new(Some(Box::new(DefaultCommandImpl)));
+    c.add(Box::new(cmd_genkey::CommandImpl));
+    c.add(Box::new(cmd_credit_create::CommandImpl));
+    c.add(Box::new(cmd_credit_issue::CommandImpl));
+    c.add(Box::new(cmd_credit_transfer::CommandImpl));
+    c.add(Box::new(cmd_credit_query::CommandImpl));
+    c.add(Box::new(cmd_credit_queryall::CommandImpl));
+
+    c.run()?;
+    Ok(())
 }