diff --git a/rhino/src/main/java/com/script/AbstractScriptEngine.kt b/rhino/src/main/java/com/script/AbstractScriptEngine.kt
index aa32073c9..1a454d464 100644
--- a/rhino/src/main/java/com/script/AbstractScriptEngine.kt
+++ b/rhino/src/main/java/com/script/AbstractScriptEngine.kt
@@ -42,15 +42,11 @@ abstract class AbstractScriptEngine(val bindings: Bindings? = null) : ScriptEngi
     }
 
     override fun put(key: String, value: Any?) {
-        val nn = getBindings(100)
-        if (nn != null) {
-            nn[key] = value
-        }
+        getBindings(100)?.put(key, value)
     }
 
     override fun get(key: String): Any? {
-        val nn = getBindings(100)
-        return nn?.get(key)
+        return getBindings(100)?.get(key)
     }
 
     override fun eval(script: String, scope: Scriptable): Any? {
diff --git a/rhino/src/main/java/com/script/ScriptException.kt b/rhino/src/main/java/com/script/ScriptException.kt
index 4737c2222..3053826b6 100644
--- a/rhino/src/main/java/com/script/ScriptException.kt
+++ b/rhino/src/main/java/com/script/ScriptException.kt
@@ -43,12 +43,12 @@ class ScriptException : Exception {
             if (fileName == null) {
                 return ret!!
             }
-            var ret2 = ret + " in " + fileName
+            var ret2 = "$ret in $fileName"
             if (lineNumber != -1) {
-                ret2 = ret2 + " at line number " + lineNumber
+                ret2 = "$ret2 at line number $lineNumber"
             }
             return if (columnNumber != -1) {
-                ret2 + " at column number " + columnNumber
+                "$ret2 at column number $columnNumber"
             } else ret2
         }
 }
\ No newline at end of file
diff --git a/rhino/src/main/java/com/script/SimpleBindings.kt b/rhino/src/main/java/com/script/SimpleBindings.kt
index 7fdf28853..d7f32086e 100644
--- a/rhino/src/main/java/com/script/SimpleBindings.kt
+++ b/rhino/src/main/java/com/script/SimpleBindings.kt
@@ -8,15 +8,11 @@ class SimpleBindings @JvmOverloads constructor(
 ) : Bindings {
 
     override fun put(key: String, value: Any?): Any? {
-        checkKey(key)
         return map.put(key, value)
     }
 
     override fun putAll(from: Map<out String, Any?>) {
-        for ((key, value) in from) {
-            checkKey(key)
-            this[key] = value
-        }
+        map.putAll(from)
     }
 
     override fun clear() {
@@ -24,7 +20,6 @@ class SimpleBindings @JvmOverloads constructor(
     }
 
     override fun containsKey(key: String): Boolean {
-        checkKey(key)
         return map.containsKey(key)
     }
 
@@ -36,7 +31,6 @@ class SimpleBindings @JvmOverloads constructor(
         get() = map.entries
 
     override operator fun get(key: String): Any? {
-        checkKey(key)
         return map[key]
     }
 
@@ -48,7 +42,6 @@ class SimpleBindings @JvmOverloads constructor(
         get() = map.keys
 
     override fun remove(key: String): Any? {
-        checkKey(key)
         return map.remove(key)
     }
 
@@ -58,13 +51,4 @@ class SimpleBindings @JvmOverloads constructor(
     override val values: MutableCollection<Any?>
         get() = map.values
 
-    private fun checkKey(key: Any?) {
-        if (key == null) {
-            throw NullPointerException("key can not be null")
-        }
-        if (key !is String) {
-            throw ClassCastException("key should be a String")
-        }
-        require(key != "") { "key can not be empty" }
-    }
 }
\ No newline at end of file
diff --git a/rhino/src/main/java/com/script/SimpleScriptContext.kt b/rhino/src/main/java/com/script/SimpleScriptContext.kt
index 41dca6077..db8d881d4 100644
--- a/rhino/src/main/java/com/script/SimpleScriptContext.kt
+++ b/rhino/src/main/java/com/script/SimpleScriptContext.kt
@@ -36,7 +36,7 @@ open class SimpleScriptContext : ScriptContext {
         if (engineScope.containsKey(name)) {
             return this.getAttribute(name, 100)
         }
-        return if (globalScope == null || !globalScope!!.containsKey(name)) {
+        return if (globalScope?.containsKey(name) != true) {
             null
         } else this.getAttribute(name, 200)
     }
@@ -47,9 +47,7 @@ open class SimpleScriptContext : ScriptContext {
                 return engineScope[name]
             }
             200 -> {
-                return if (globalScope != null) {
-                    globalScope!![name]
-                } else null
+                return globalScope?.get(name)
             }
         }
         throw IllegalArgumentException("Illegal scope value.")
@@ -58,14 +56,10 @@ open class SimpleScriptContext : ScriptContext {
     override fun removeAttribute(name: String, scope: Int): Any? {
         when (scope) {
             100 -> {
-                return if (getBindings(100) != null) {
-                    getBindings(100)!!.remove(name)
-                } else null
+                return getBindings(100)?.remove(name)
             }
             200 -> {
-                return if (getBindings(200) != null) {
-                    getBindings(200)!!.remove(name)
-                } else null
+                return getBindings(200)?.remove(name)
             }
         }
         throw IllegalArgumentException("Illegal scope value.")
@@ -89,7 +83,7 @@ open class SimpleScriptContext : ScriptContext {
         if (engineScope.containsKey(name)) {
             return 100
         }
-        return if (globalScope == null || !globalScope!!.containsKey(name)) {
+        return if (globalScope?.containsKey(name) != true) {
             -1
         } else 200
     }