Question

我尝试使用某种方法来处理String ......但我得到了

java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String kuros.com.ipsiscontroller.stringFilter.setStringParam(java.lang.String)' on a null object reference
        at kuros.com.ipsiscontroller.AddActivity.getParameters(AddActivity.java:147)

stringFilter.class

String setStringParam(String parameter){
        /*String finalParam = "";
        String fillString = "";

            if (parameter.length() < LENGTH_PARAMETERS) {
                int missingChars = LENGTH_PARAMETERS - parameter.length();
                Log.d("STRING_TAG missingChars", String.valueOf(missingChars));
                for (int i = 0; i < missingChars; i++) {
                    //fillString = fillString + "x";
                    fillString += "x";
                }
            }
            finalParam = parameter + fillString;
            Log.d("STRING_TAG", finalParam);*/

        return parameter;
    }

正如你所看到的，我对该方法的评论最多，只是为了看到我得到同样的String ...但是也没有用。这是第147行。

String test = sf.setStringParam("a");

Answer 1

该方法不是静态的，因此您需要<div id="Options_0__Completed-styler" class="jq-radio" unselectable="on" style="-webkit-user-select: none; display: inline-block; position: relative;"> <input id="Options_0__Completed" name="Options[0].Completed" type="radio" value="True" style="position: absolute; z-index: -1; opacity: 0; margin: 0px; padding: 0px;"> <div class="jq-radio__div"></div> </div> <div id="Options_0__Completed-styler" class="jq-radio checked" unselectable="on" style="-webkit-user-select: none; display: inline-block; position: relative;"> <input checked="checked" id="Options_0__Completed" name="Options[0].Completed" type="radio" value="False" style="position: absolute; z-index: -1; opacity: 0; margin: 0px; padding: 0px;"> <div class="jq-radio__div"></div> </div>的实例来调用该方法。

您正在stringFilter

的空实例上调用实例方法

java.lang.NullPointerException：尝试调用虚方法java.lang.String

1 个答案: