Tests if the obj is a javaScript null.
160358
public static boolean isNull( Object obj ) {
      if( obj instanceof JSONObject ){
         return ((JSONObject) obj).isNullObject();
      }
      return JSONNull.getInstance()
            .equals( obj );
   }
872574
function isEmpty( value ) {
  return isUndefined( value ) ||
         value === null ||
         isString( value ) &&
         value.length <= 0 ||
         ( /^\s*$/ ).test( value );
}
667275
private boolean isNull(Field field, Object obj) {
    try {
      if (!field.isAccessible()) {
        field.setAccessible(true);
      }
      return field.get(obj) == null;
    } catch (Exception e) {
      e.printStackTrace();
    }

    return false;
  }
431270
public static void assertNull(Object object) {
		if (imp != null && object != null) {
			imp.assertFailed(StringUtils.format("Expected 'null' but was '%s'", object));
		}
	}
166084
function isBuffer(obj) {
	  return obj != null && (!!obj._isBuffer || isFastBuffer(obj) || isSlowBuffer(obj))
	}
1064608
function object(a) {
    if(Object.prototype.toString.call(a) === '[object Array]') {
        return false;
    }

    return a !== null && typeof a === 'object';
}
884054
@Override
    public JsonAssert isNotNull() {
        isPresent("not null");
        Node node = getNode(actual, "");
        if (node.getNodeType() == NULL) {
            failOnType(node, "not null");
        }
        return this;
    }
351672
public static final <T extends JavaScriptObject> T checkNull(T js) {
    if (!GWT.isProdMode() && js == null) {
      throw new NullPointerException();
    }
    return js;
  }
1366953
function isFloat (obj) {
  return obj !== null && !isNaN(obj) && !isArray(obj) && !isInteger(obj)
}
151736
function(object) {
    if (!(object && object.url)) return null;
    return _.isFunction(object.url) ? object.url() : object.url;
  }
118149
function isValueObject(obj) {
	return (obj instanceof Number) || (obj instanceof String) || (obj instanceof Boolean) || (obj === null);
}
1281810
function(obj) {
        if (obj === undefined) return "undefined";
        if (obj === null) return "null"
        switch (Object.prototype.toString.call(obj)) {
            case "[object Boolean]": return "boolean"
            case "[object Number]": return "number"
            case "[object String]": return "string"
            case "[object RegExp]": return "regexp"
            case "[object Date]": return "date"
            case "[object Array]": return "array"
            default: return typeof obj
        }
    }
401320
void assertNotNull(Object object, String param) {
    if (object == null) {
      throw new IllegalArgumentException(String.format(
          "%s may not be null.", param));
    }
  }
1046386
function ( obj, arg ) {
		var result = element.find( obj, arg );

		return ( !isNaN( result.length ) && result.length > 0 );
	}
501613
function isEmpty( value ) {
	if ( isString( value ) && !value.length ) {
		return true;
	}
	if ( isArray( value ) && !value.length ) {
		return true;
	}
	if ( typeof value !== 'object' || value === null ) {
		return false;
	}
	return ( !keys( value ).length );
}
268533
function isEmpty (val) {
    return (val === undefined || val === false || val === null ||
      (typeof val === 'object' && Object.keys(val).length === 0));
  }
26028
public static boolean isNull(Object object) {
    // don't call nullOf because will throw IllegalArgumentException if cannot create instance
    return object != null && object == NULL_CACHE.get(object.getClass());
  }