update doc

en/_sources/http-api.md.txt

@@ -26,9 +26,9 @@ http api.
 ```json
 {
   "action": "exec",
-  "requestId": "req112"
-  "sessionId": "94766d3c-8b39-42d3-8596-98aee3ccbefb"
-  "consumerId": "955dbd1325334a84972b0f3ac19de4f7_2"
+  "requestId": "req112",
+  "sessionId": "94766d3c-8b39-42d3-8596-98aee3ccbefb",
+  "consumerId": "955dbd1325334a84972b0f3ac19de4f7_2",
   "command": "version",
   "execTimeout": "10000"
 }
@@ -614,7 +614,48 @@ receive this `enhancer` result. It may happen that the result of
 `enhancer` is successful, but there is no hit method. The client can
 prompt the user according to the result of `enhancer`.
 
-### Others
+### Cases
+
+#### Get classpath of Java application
+
+Get system properties of the Java application through Http api and
+extract the value of `java.class.path`.
+
+```bash
+json_data=$(curl -Ss -XPOST http://localhost:8563/api -d '
+{
+  "action":"exec",
+  "command":"sysprop"
+}')
+```
+
+* Extract value with `sed`:
+
+```bash
+class_path=$(echo $json_data | tr -d '\n' | sed 's/.*"java.class.path":"\([^"]*\).*/\1/')
+echo "classpath: $class_path"
+```
+
+* Extract value with `json_pp/awk`:
+
+```bash
+class_path=$(echo $json_data | tr -d '\n' | json_pp | grep java.class.path | awk -F'"' '{ print $4 }')
+echo "classpath: $class_path"
+```
+
+Output:
+
+```
+classpath: demo-arthas-spring-boot.jar
+```
+
+NOTE:
+
+* `echo $json_data | tr -d '\n'` : Delete line breaks (the value of
+  `line.separator`) to avoid affecting the processing of `sed`/`json_pp`
+  commands.
+* `awk -F'"' '{ print $4 }'` : Use double quote as delimiter
+
 
 <a id="change_watch_value_to_map"></a>
 #### Make watch command output a map object

en/_sources/jad.md.txt

@@ -1,6 +1,8 @@
 jad
 ===
 
+[`jad` online tutorial](https://arthas.aliyun.com/doc/arthas-tutorials?language=en&id=command-jad)
+
 > Decompile the specified classes.
 
 `jad` helps to decompile the byte code running in JVM to the source code to assist you to understand the logic behind better.

en/_sources/logger.md.txt

@@ -1,6 +1,8 @@
 logger
 ===
 
+[`logger` online tutorial](https://arthas.aliyun.com/doc/arthas-tutorials?language=en&id=command-logger)
+
 > Print the logger information, update the logger level
 
 ### Usage

en/_sources/mc.md.txt

@@ -1,6 +1,8 @@
 mc
 ===
 
+[`mc-redefine` online tutorial](https://arthas.aliyun.com/doc/arthas-tutorials?language=en&id=command-mc-redefine)
+
 > Memory compiler, compiles `.java` files into `.class` files in memory.
 
 ```bash

en/_sources/profiler.md.txt

@@ -1,12 +1,25 @@
 profiler
 ===
 
+[`profiler` online tutorial](https://arthas.aliyun.com/doc/arthas-tutorials.html?language=en&id=command-profiler)
+
 > Generate a flame graph using [async-profiler](https://github.com/jvm-profiling-tools/async-profiler)
 
 The `profiler` command supports generate flame graph for application hotspots.
 
 The basic usage of the `profiler` command is `profiler action [actionArg]`
 
+### Supported Options
+
+|Name|Specification|
+|---:|:---|
+|*action*|Action to execute|
+|*actionArg*|Attribute name pattern|
+|[i:]|sampling interval in ns (default: 10'000'000, i.e. 10 ms)|
+|[f:]|dump output to specified directory|
+|[d:]|run profiling for specified seconds|
+|[e:]|which event to trace (cpu, alloc, lock, cache-misses etc.), default value is cpu|
+
 ### Start profiler
 
 ```

en/_sources/redefine.md.txt

@@ -1,10 +1,20 @@
 redefine
 ========
 
+[`mc-redefine` online tutorial](https://arthas.aliyun.com/doc/arthas-tutorials?language=en&id=command-mc-redefine)
+
 > Load the external `*.class` files to re-define the loaded classes in JVM.
 
 Reference: [Instrumentation#redefineClasses](https://docs.oracle.com/javase/8/docs/api/java/lang/instrument/Instrumentation.html#redefineClasses-java.lang.instrument.ClassDefinition...-)
 
+### Frequently asked questions
+
+* The class of `redefine` cannot modify, add or delete the field and method of the class, including method parameters, method names and return values.
+
+* If `mc` fails, you can compile the class file in the local development environment, upload it to the target system, and use `redefine` to hot load the class.
+
+* At present, `redefine` conflicts with `watch / trace / jad / tt` commands. Reimplementing `redefine` function in the future will solve this problem.
+
 > Notes: Re-defined classes cannot be restored. There are chances that redefining may fail due to some reasons, for example: there's new field introduced in the new version of the class, pls. refer to JDK's documentation for the limitations.
 
 > The `reset` command is not valid for classes that have been processed by `redefine`. If you want to reset, you need `redefine` the original bytecode.

en/_sources/sc.md.txt

@@ -1,6 +1,8 @@
 sc
 ==
 
+[`sc` online tutorial](https://arthas.aliyun.com/doc/arthas-tutorials?language=en&id=command-sc)
+
 > Search classes loaded by JVM.
 
 `sc` stands for search class. This command can search all possible classes loaded by JVM and show their information. The supported options are: `[d]`、`[E]`、`[f]` and `[x:]`.
@@ -15,6 +17,8 @@ sc
 |`[E]`|turn on regex match, the default behavior is wildcards match|
 |`[f]`|print the fields info of the current class, MUST be used with `-d` together|
 |`[x:]`|specify the depth of recursive traverse the static fields, the default value is '0' - equivalent to use `toString` to output|
+|`[c:]`|The hash code of the special class's classLoader|
+|`[n:]`|Maximum number of matching classes with details (100 by default)|
 
 > *class-patten* supports full qualified class name, e.g. com.taobao.test.AAA and com/taobao/test/AAA. It also supports the format of 'com/taobao/test/AAA', so that it is convenient to directly copy class name from the exception stack trace without replacing '/' to '.'. <br/><br/>
 > `sc` turns on matching sub-class match by default, that is, `sc` will also search the sub classes of the target class too. If exact-match is desired, pls. use `options disable-sub-class true`.

en/_sources/sm.md.txt

@@ -1,6 +1,8 @@
 sm
 ==
 
+[`sm` online tutorial](https://arthas.aliyun.com/doc/arthas-tutorials?language=en&id=command-sm)
+
 > Search method from the loaded classes.
 
 `sm` stands for search method. This command can search and show method information from all loaded classes. `sm` can only view the methods declared on the target class, that is, methods from its parent classes are invisible.
@@ -14,6 +16,8 @@ sm
 |*method-pattern*|pattern for method name|
 |`[d]`|print the details of the method|
 |`[E]`|turn on regex matching while the default mode is wildcard matching|
+|`[c:]`|The hash code of the special class's classLoader|
+|`[n:]`|Maximum number of matching classes with details (100 by default)|
 
 ### Usage