教你如何用AST语法树对代码“动手脚”

void someMethod(){
    String rst=callAnotherMethod();
    LogUtil.log(TAG,”这里是一条非常非常长，比唐僧还啰嗦的日志信息描述，但是我短一点还不方便进行错误日志分析，调用callSomeMethod返回的结果是:”+rst);
……
}

void someMethod(){
    String rst=callAnotherMethod();
    LogUtil.log(TAG,”<-(1)->”+rst);
……
}

val JavaSources:List<Path> //Java source file path list
OracleJdkParser().parse(JavaSources)
 .forEach { unit ->
   unit.refactor(Consumer { tx ->
       unit.classes.forEach { clazz ->
           clazz.findMethodCalls("demo.LogUtillog(String,String)").forEach{ mc ->
               val args = mc.args.args
               val expression = args[1]
               logMapping.refactor(clazz, expression, tx)
            }
       }
        val fix = tx.fix()
        val newFile = ...//dist Source File ...
       newFile.writeText(fix.print())
    })
}
fun refactor(clazz: Tr.ClassDecl, target: Expression, refactor: Refactor, originSb: StringBuilder): Unit {
        when(target) {
           is Tr.Literal -> {
               refactor.changeLiteral(target) { t ->
                        val id = pushMapping(clazz, t) //pushLiteral to mapping and return id
                        originSb.append("$PREFIX$t$POSTFIX")
                        return@changeLiteral rewriteNormal(id)
                    }
               }
           }
           is Tr.Binary -> {
               refactor(clazz, target.left, refactor, originSb)
               refactor(clazz, target.right, refactor, originSb)
            }
       }
}

val normalPattern = Pattern.compile("(<!--\[([^|]+)\|(\d+)_(\d+):(\d+)]-->)")
logFiles.forEach { file ->
file.bufferedReader().use { reader ->
   File(distDir, file.name).bufferedWriter().use { writer ->
        var line: String
        while(true){
           line = reader.readLine()
           if (line == null) break
           val matcher = normalPattern.matcher(line)
           var newLine: String = line + ""
           while (matcher.find()) { //normal recover
               val token = matcher.group(1)
               val projectName = matcher.group(2)
               val appVersion = matcher.group(3).toInt()
               val targetVersion = matcher.group(4).toInt()
               val id = matcher.group(5).toLong()
               val replaceMent = findReplacement(projectName,appVersion, targetVersion, id)
               newLine = newLine.replace(token, replaceMent)
           }
           writer.write(newLine)
           writer.newLine()
       }
     }
 }

try{
    value = Boolean.parseBoolean(str);
} catch (Throwable e) {
    // #debug
    e.printStackTrace();
}

try{
    value = Boolean.parseBoolean(str);
} catch (Throwable e) {
}
void m(){
    relaseCall();
    //#mdebug
    String info="some debug infomation";
    LogUtil.log(info);
    //#enddebug
}

void m(){
    relaseCall();
}

void onClick(View v){
    doSomeThing()
}
void onClick(View v){
    RUtil.recordClick(v); 
    doSomeThing();
}