refactor: simplify and uniform the codes

- remove declare for global vars, more consistent
- use upper-case var name for global readonly vars
- unset temp global vars after use

Author: oldratlee

bin/a2l

@@ -43,7 +43,7 @@ progVersion() {
 # parse options
 ################################################################################
 
-declare -a args=()
+args=()
 while (($# > 0)); do
   case "$1" in
   -h | --help)

bin/ap

@@ -103,7 +103,7 @@ progVersion() {
 # parse options
 ################################################################################
 
-declare -a files=()
+files=()
 while (($# > 0)); do
   case "$1" in
   -h | --help)
@@ -129,8 +129,7 @@ while (($# > 0)); do
 done
 
 # if files is empty, use "."
-files=("${files[@]:-.}")
-readonly files
+readonly files=("${files[@]:-.}")
 
 ################################################################################
 # biz logic

bin/c

@@ -83,7 +83,7 @@ progVersion() {
 
 quiet=false
 keep_eol=false
-declare -a target_command=()
+target_command=()
 while (($# > 0)); do
   case "$1" in
   -k | --keep-eol)

bin/coat

@@ -40,7 +40,7 @@ EOF
   exit
 }
 
-declare -a args=("$@")
+args=("$@")
 # check arguments in reverse, so last option wins.
 for ((idx = $# - 1; idx >= 0; --idx)); do
   [ "${args[idx]}" = --help ] && usage

bin/cp-into-docker-run

@@ -120,7 +120,7 @@ docker_workdir=
 docker_tmpdir=/tmp
 docker_command_cp_path=
 verbose=false
-declare -a args=()
+args=()
 
 while (($# > 0)); do
   case "$1" in

bin/echo-args

@@ -20,16 +20,15 @@ digitCount() {
 digit_count=$(digitCount $#)
 readonly arg_count=$# digit_count
 
-readonly red='\e[1;31m' blue='\e[1;36m' color_reset='\e[0m'
-
+readonly RED='\e[1;31m' BLUE='\e[1;36m' COLOR_RESET='\e[0m'
 printArg() {
   local idx=$1 value=$2
 
   # if stdout is a terminal, turn on color output.
   #   '-t' check: is a terminal?
   #   check isatty in bash https://stackoverflow.com/questions/10022323
   if [ -t 1 ]; then
-    printf "%${digit_count}s/%s: ${red}[${blue}%s${red}]${color_reset}\n" "$idx" "$arg_count" "$value"
+    printf "%${digit_count}s/%s: ${RED}[${BLUE}%s${RED}]${COLOR_RESET}\n" "$idx" "$arg_count" "$value"
   else
     printf "%${digit_count}s/%s: [%s]\n" "$idx" "$arg_count" "$value"
   fi

bin/find-in-jars

@@ -38,34 +38,34 @@ readonly PROG_VERSION='2.x-dev'
 # util functions
 ################################################################################
 
-readonly color_reset='\e[0m'
-
-# How to delete line with echo?
-# https://unix.stackexchange.com/questions/26576
-#
-# terminal escapes: http://ascii-table.com/ansi-escape-sequences.php
-# In particular, to clear from the cursor position to the beginning of the line:
-# echo -e "\033[1K"
-# Or everything on the line, regardless of cursor position:
-# echo -e "\033[2K"
-readonly clear_line='\e[2K\r'
+readonly COLOR_RESET='\e[0m'
 
 redPrint() {
   # if stdout is a terminal, turn on color output.
   #   '-t' check: is a terminal?
   #   check isatty in bash https://stackoverflow.com/questions/10022323
   if [ -t 1 ]; then
-    printf "\e[1;31m%s$color_reset\n" "$*"
+    printf "\e[1;31m%s$COLOR_RESET\n" "$*"
   else
     printf '%s\n' "$*"
   fi
 }
 
+# How to delete line with echo?
+# https://unix.stackexchange.com/questions/26576
+#
+# terminal escapes: http://ascii-table.com/ansi-escape-sequences.php
+# In particular, to clear from the cursor position to the beginning of the line:
+# echo -e "\033[1K"
+# Or everything on the line, regardless of cursor position:
+# echo -e "\033[2K"
+readonly LINE_CLEAR='\e[2K\r'
+
 # Getting console width using a bash script
 # https://unix.stackexchange.com/questions/299067
 #
 # NOTE: DO NOT declare columns var as readonly in ONE line!
-[ -t 2 ] && columns=$(stty size | awk '{print $2}')
+[ -t 2 ] && COLUMNS=$(stty size | awk '{print $2}')
 
 printResponsiveMessage() {
   if ! $show_responsive || [ ! -t 2 ]; then
@@ -74,15 +74,15 @@ printResponsiveMessage() {
 
   local content=$*
   # http://www.linuxforums.org/forum/red-hat-fedora-linux/142825-how-truncate-string-bash-script.html
-  printf %b%s "$clear_line" "${content:0:columns}" >&2
+  printf %b%s "$LINE_CLEAR" "${content:0:COLUMNS}" >&2
 }
 
 clearResponsiveMessage() {
   if ! $show_responsive || [ ! -t 2 ]; then
     return
   fi
 
-  printf %b "$clear_line" >&2
+  printf %b "$LINE_CLEAR" >&2
 }
 
 die() {
@@ -155,9 +155,9 @@ progVersion() {
 # parse options
 ################################################################################
 
-declare -a dirs=()
-declare -a extensions=()
-declare -a args=()
+dirs=()
+extensions=()
+args=()
 
 separator='!'
 regex_mode=-E
@@ -250,7 +250,7 @@ readonly extensions=${extensions:-jar}
 ((${#args[@]} > 1)) && usage 1 "More than 1 file pattern: ${args[*]}"
 readonly pattern=${args[0]}
 
-declare -a tmp_dirs=()
+tmp_dirs=()
 for d in "${dirs[@]}"; do
   [ -e "$d" ] || die "file $d(specified by option -d) does not exist!"
   [ -d "$d" ] || die "file $d(specified by option -d) exists but is not a directory!"
@@ -262,13 +262,15 @@ done
 # set dirs to Absolute Path
 $use_absolute_path && dirs=("${tmp_dirs[@]}")
 readonly dirs
+unset d tmp_dirs
 
 # convert extensions to find -iname options
 find_iname_options=()
 for e in "${extensions[@]}"; do
   find_iname_options=(${find_iname_options[@]:+"${find_iname_options[@]}" -o} -iname "*.$e")
 done
 readonly find_iname_options
+unset e
 
 ################################################################################
 # Check the existence of command for listing zip entry!
@@ -353,8 +355,9 @@ searchJarFiles() {
   printf '%s\n' "$jar_files"
 }
 
+readonly JAR_COLOR='\e[1;35m' SEP_COLOR='\e[1;32m'
 __outputResultOfJarFile() {
-  local jar_file=$1 file jar_color='\e[1;35m' sep_color='\e[1;32m'
+  local jar_file=$1 file
   # shellcheck disable=SC2206
   local grep_opt_args=("$regex_mode" ${ignore_case_option:-} ${grep_color_option:-} -- "$pattern")
 
@@ -374,7 +377,7 @@ __outputResultOfJarFile() {
 
     clearResponsiveMessage
     if [ -t 1 ]; then
-      printf "$jar_color%s$color_reset\n" "$jar_file"
+      printf "$JAR_COLOR%s$COLOR_RESET\n" "$jar_file"
     else
       printf '%s\n' "$jar_file"
     fi
@@ -386,7 +389,7 @@ __outputResultOfJarFile() {
     } | while read -r file; do
       clearResponsiveMessage
       if [ -t 1 ]; then
-        printf "$jar_color%s$sep_color%s$color_reset%s\n" "$jar_file" "$separator" "$file"
+        printf "$JAR_COLOR%s$SEP_COLOR%s$COLOR_RESET%s\n" "$jar_file" "$separator" "$file"
       else
         printf '%s\n' "$jar_file$separator$file"
       fi

bin/rp

@@ -102,7 +102,7 @@ progVersion() {
 # parse options
 ################################################################################
 
-declare -a files=()
+files=()
 while (($# > 0)); do
   case "$1" in
   -h | --help)

bin/show-busy-java-threads

@@ -47,7 +47,7 @@ readonly USER
 ################################################################################
 
 # NOTE: $'foo' is the escape sequence syntax of bash
-readonly nl=$'\n' # new line
+readonly NL=$'\n' # new line
 
 colorPrint() {
   local color=$1
@@ -151,7 +151,7 @@ usage() {
   (($# > 0)) && shift
   local -r out=$(((exit_code != 0) + 1))
 
-  (($# > 0)) && colorPrint 31 "$*$nl" >&"$out"
+  (($# > 0)) && colorPrint 31 "$*$NL" >&"$out"
 
   cat >&"$out" <<EOF
 Usage: ${PROG} [OPTION]... [delay [count]]
@@ -352,18 +352,18 @@ if [ -n "$jstack_path" ]; then
 elif [ -n "$JAVA_HOME" ]; then
   # 2. search jstack under JAVA_HOME
   if [ -f "$JAVA_HOME/bin/jstack" ]; then
-    [ -x "$JAVA_HOME/bin/jstack" ] || die "found \$JAVA_HOME/bin/jstack($JAVA_HOME/bin/jstack) is NOT executable!${nl}Use -s option set jstack path manually."
+    [ -x "$JAVA_HOME/bin/jstack" ] || die "found \$JAVA_HOME/bin/jstack($JAVA_HOME/bin/jstack) is NOT executable!${NL}Use -s option set jstack path manually."
     jstack_path="$JAVA_HOME/bin/jstack"
   elif [ -f "$JAVA_HOME/../bin/jstack" ]; then
-    [ -x "$JAVA_HOME/../bin/jstack" ] || die "found \$JAVA_HOME/../bin/jstack($JAVA_HOME/../bin/jstack) is NOT executable!${nl}Use -s option set jstack path manually."
+    [ -x "$JAVA_HOME/../bin/jstack" ] || die "found \$JAVA_HOME/../bin/jstack($JAVA_HOME/../bin/jstack) is NOT executable!${NL}Use -s option set jstack path manually."
     jstack_path="$JAVA_HOME/../bin/jstack"
   fi
 elif command -v jstack &>/dev/null; then
   # 3. search jstack under PATH
   jstack_path=$(command -v jstack)
-  [ -x "$jstack_path" ] || die "found $jstack_path from PATH is NOT executable!${nl}Use -s option set jstack path manually."
+  [ -x "$jstack_path" ] || die "found $jstack_path from PATH is NOT executable!${NL}Use -s option set jstack path manually."
 else
-  die "jstack NOT found by JAVA_HOME(${JAVA_HOME:-not set}) setting and PATH!${nl}Use -s option set jstack path manually."
+  die "jstack NOT found by JAVA_HOME(${JAVA_HOME:-not set}) setting and PATH!${NL}Use -s option set jstack path manually."
 fi
 readonly jstack_path
 

bin/taoc

@@ -40,7 +40,7 @@ EOF
   exit
 }
 
-declare -a args=("$@")
+args=("$@")
 # check arguments in reverse, so last option wins.
 for ((idx = $# - 1; idx >= 0; --idx)); do
   [ "${args[idx]}" = --help ] && usage