as.sh fix mingw support.

as.sh

@@ -8,10 +8,10 @@
 
 # program : Arthas
 #  author : Core Engine @ Taobao.com
-#    date : 2018-11-19
+#    date : 2018-11-23
 
 # current arthas script version
-ARTHAS_SCRIPT_VERSION=3.0.4.2
+ARTHAS_SCRIPT_VERSION=3.0.4.3
 
 # define arthas's home
 ARTHAS_HOME=${HOME}/.arthas
@@ -488,10 +488,14 @@ attach_jvm()
 
     echo "Attaching to ${TARGET_PID} using version ${1}..."
 
-    local opts="${ARTHAS_OPTS} ${BOOT_CLASSPATH} ${JVM_OPTS}"
+    local java_command=("${JAVA_HOME}"/bin/java)
+    if [ "${BOOT_CLASSPATH}" ]; then
+        java_command+=("${BOOT_CLASSPATH}")
+    fi
+
     if [ ${TARGET_IP} = ${DEFAULT_TARGET_IP} ]; then
-        "${JAVA_HOME}"/bin/java \
-            ${opts}  \
+        "${java_command[@]}" \
+            ${ARTHAS_OPTS} ${JVM_OPTS} \
             -jar "${arthas_lib_dir}/arthas-core.jar" \
                 -pid ${TARGET_PID} \
                 -target-ip ${TARGET_IP} \