typo: ariable name and word error.

boot/src/main/java/com/taobao/arthas/boot/Bootstrap.java

@@ -429,14 +429,14 @@ public class Bootstrap {
                             + File.separator + bootstrap.getUseVersion() + File.separator + "arthas");
             if (!specialVersionDir.exists()) {
                 // try to download arthas from remote server.
-                DownloadUtils.downArthasPackaging(bootstrap.getRepoMirror(), bootstrap.isuseHttp(),
+                DownloadUtils.downArthasPackaging(bootstrap.getRepoMirror(), bootstrap.isUseHttp(),
                                 bootstrap.getUseVersion(), ARTHAS_LIB_DIR.getAbsolutePath());
             }
             verifyArthasHome(specialVersionDir.getAbsolutePath());
             arthasHomeDir = specialVersionDir;
         }
 
-        // Try set the directory where arthas-boot.jar is located to arhtas home
+        // Try set the directory where arthas-boot.jar is located to arthas home
         if (arthasHomeDir == null) {
             CodeSource codeSource = Bootstrap.class.getProtectionDomain().getCodeSource();
             if (codeSource != null) {
@@ -470,16 +470,16 @@ public class Bootstrap {
             List<String> versionList = listNames(ARTHAS_LIB_DIR);
             Collections.sort(versionList);
 
-            String localLastestVersion = null;
+            String localLatestVersion = null;
             if (!versionList.isEmpty()) {
-                localLastestVersion = versionList.get(versionList.size() - 1);
+                localLatestVersion = versionList.get(versionList.size() - 1);
             }
 
-            String remoteLastestVersion = DownloadUtils.readLatestReleaseVersion();
+            String remoteLatestVersion = DownloadUtils.readLatestReleaseVersion();
 
             boolean needDownload = false;
-            if (localLastestVersion == null) {
-                if (remoteLastestVersion == null) {
+            if (localLatestVersion == null) {
+                if (remoteLatestVersion == null) {
                     // exit
                     AnsiLog.error("Can not find Arthas under local: {} and remote repo mirror: {}", ARTHAS_LIB_DIR,
                             bootstrap.getRepoMirror());
@@ -490,23 +490,23 @@ public class Bootstrap {
                     needDownload = true;
                 }
             } else {
-                if (remoteLastestVersion != null) {
-                    if (localLastestVersion.compareTo(remoteLastestVersion) < 0) {
-                        AnsiLog.info("local lastest version: {}, remote lastest version: {}, try to download from remote.",
-                                        localLastestVersion, remoteLastestVersion);
+                if (remoteLatestVersion != null) {
+                    if (localLatestVersion.compareTo(remoteLatestVersion) < 0) {
+                        AnsiLog.info("local latest version: {}, remote latest version: {}, try to download from remote.",
+                                localLatestVersion, remoteLatestVersion);
                         needDownload = true;
                     }
                 }
             }
             if (needDownload) {
                 // try to download arthas from remote server.
-                DownloadUtils.downArthasPackaging(bootstrap.getRepoMirror(), bootstrap.isuseHttp(),
-                                remoteLastestVersion, ARTHAS_LIB_DIR.getAbsolutePath());
-                localLastestVersion = remoteLastestVersion;
+                DownloadUtils.downArthasPackaging(bootstrap.getRepoMirror(), bootstrap.isUseHttp(),
+                        remoteLatestVersion, ARTHAS_LIB_DIR.getAbsolutePath());
+                localLatestVersion = remoteLatestVersion;
             }
 
             // get the latest version
-            arthasHomeDir = new File(ARTHAS_LIB_DIR, localLastestVersion + File.separator + "arthas");
+            arthasHomeDir = new File(ARTHAS_LIB_DIR, localLatestVersion + File.separator + "arthas");
         }
 
         verifyArthasHome(arthasHomeDir.getAbsolutePath());
@@ -785,7 +785,7 @@ public class Bootstrap {
         return repoMirror;
     }
 
-    public boolean isuseHttp() {
+    public boolean isUseHttp() {
         return useHttp;
     }
 

core/src/main/java/com/taobao/arthas/core/command/basic1000/HistoryCommand.java

@@ -39,7 +39,7 @@ public class HistoryCommand extends AnnotatedCommand {
     }
 
     @Argument(index = 0, argName = "n", required = false)
-    @Description("how many history commnads to display")
+    @Description("how many history commands to display")
     public void setNumber(int n) {
         this.n = n;
     }

core/src/main/java/com/taobao/arthas/core/command/basic1000/JFRCommand.java

@@ -322,7 +322,7 @@ public class JFRCommand extends AnnotatedCommand {
                 try {
                     r.setDestination(Paths.get(getFilename()));
                 } catch (IOException e) {
-                    process.end(-1, "Failed to stop" + r.getName() + ". Could not set destination for " + filename + "to file" + e.getMessage());
+                    process.end(-1, "Failed to stop " + r.getName() + ". Could not set destination for " + filename + "to file" + e.getMessage());
                 }
 
                 r.stop();
@@ -353,7 +353,7 @@ public class JFRCommand extends AnnotatedCommand {
             try {
                 return Long.parseLong(s);
             } catch (Exception e) {
-                throw new NumberFormatException("'" + s + "' is not a valid size. Shoule be numeric value followed by a unit, i.e. 20M. Valid units k, M, G");
+                throw new NumberFormatException("'" + s + "' is not a valid size. Should be numeric value followed by a unit, i.e. 20M. Valid units k, M, G");
             }
         }
     }