Question

这可能是一个愚蠢的问题，但我在这里感到困惑。我有以下情况：

Main.java

var tbody = $('.zaawansowana_edycja').find('tbody');
for (var x = 0, len = Object.keys(r.konfiguracja.data).length; x < len; x++) {
    (function(idx) {
        var obj = r.konfiguracja.data[idx];
        var obj_y = $('.konfiguratorHeaderTable').find('td[data-krzeselkoid="' + obj.id_krzesla + '"]').index();
        var konf_cache = tbody.find('tr.konfiguratorAttr[key="' + obj.TKA1.id_tkaniny + '|' + obj.TKA2.id_tkaniny + '"]');

    if (!konf_cache.length) {
        var newHtml = $('<tr>');
        newHtml.addClass('konfiguratorAttr').attr('key', obj.TKA1.id_tkaniny + '|' + obj.TKA2.id_tkaniny);

        for (var t1 = 0; t1 < $('.konfiguratorHeaderTable').find('.obr').find('td').length; t1++) {
            newHtml.append('<td>');
        }

        tbody.append(newHtml);
    }

    konf_cache.find('td:first').html('<div class="col-sm-12"><select>' + selectHtml.html() + '</select></div><div class="col-sm-12"><select>' + selectHtml.html() + '</select></div>');

    var h2 = $('<div>');
    h2.addClass('col-sm-12');
    h2.append($('<input>').attr('type', 'text'));
    h2.append($('<input>').attr('type', 'text'));
    h2.append($('<input>').attr('type', 'text'));
    h2.append($('<input>').attr('type', 'text'));
    h2.append($('<input>').attr('type', 'text'));
    h2.append($('<input>').attr('type', 'text'));
    h2.append($('<input>').attr('type', 'text'));
    h2.append($('<input>').attr('type', 'text'));
    h2.append($('<input>').attr('type', 'text'));
    h2.append($('<input>').attr('type', 'text'));
    h2.append($('<input>').attr('type', 'text'));
    h2.append($('<input>').attr('type', 'text'));
    h2.append($('<input>').attr('type', 'text'));
    konf_cache.find('td').eq(obj_y).append(h2.html());

})(x);
}

XmlBuilder.java

public class Main {

    public static void main (String args[]){
        GenericTag[] arr = new GenericTag[2];
        arr[0] = new Authentication("", "", "", "");
        arr[1] = new Document("", "", "", "");
        byte[] foo= Base64.decodeBase64(XmlBuilder.generate(arr));
        System.out.println(new String(foo));
    }

我无法让它发挥作用。编译器说无法将Authentication和Document都解析为类型。如果我明确说明public final class XmlBuilder { private static final String OPEN_TAG = ""; private static final String CLOSE_TAG = ""; public static byte[] generate(GenericTag[] tags){ String xml = OPEN_TAG; for(int i=0; i<tags.length; i++){ xml += tags[i].xml; } xml += CLOSE_TAG; return Base64.encodeBase64(xml.getBytes()); } public interface GenericTag{ public String getXml(); } public class Authentication implements GenericTag{ private static final String OPEN_TAG = "<authentication>"; private static final String CLOSE_TAG = "</autentication>"; //some tags public Authentication (/*some parameters*/){ xml = OPEN_TAG; //xml building xml += CLOSE_TAG; } @Override public String getXml() { return xml; } } public class Document implements GenericTag{ private static final String OPEN_TAG = "<document>"; private static final String CLOSE_TAG = "</document>"; //some tags public String xml; public Documento (/*some params*/){ xml = OPEN_TAG; //xml building xml += CLOSE_TAG; } @Override public String getXml() { return xml; } } }，则说明

new XmlBuilder.Authentication

我在这里做错了什么？

Answer 1

制作课程Authentication和Document public static。由于这些不是static，因此您只能从XmlBuilder实例中实例化它们。

Java inner class and static nested class - 您可以在此处找到更多信息

Answer 2

您尝试创建抽象类的内部类的实例。使这个类独立。

Answer 3

首先，你有一些语法错误，其次，你需要使内部类静态，这样它们就不依赖于外部实例而是独立存在。您需要重构它们，以便不依赖于父类的任何字段。更好的风格是将它们放在自己的源文件中，但在一个文件中，代码的编译版本将是：

import java.util.Base64;

public abstract class XmlBuilder {
    private static final String OPEN_TAG = "";
    private static final String CLOSE_TAG = "";
    private String xml;

    public static byte[] generate(GenericTag[] tags){

        String xml = OPEN_TAG;
        for(int i=0; i<tags.length; i++){
            xml += tags[i].getXml();
        }
        xml += CLOSE_TAG;

        return Base64.getEncoder().encode(xml.getBytes());
    }

    public static interface GenericTag{
        public String getXml();
    }

    public static class Authentication implements GenericTag{
        private static final String OPEN_TAG = "<authentication>";
        private static final String CLOSE_TAG = "</autentication>";
        private static String xml;
        //some tags

        public Authentication (/*some parameters*/){
            xml = OPEN_TAG;
            //xml building
            xml += CLOSE_TAG;
        }

        @Override
        public String getXml() {
            return xml;
        }
    }

    public static class Document implements GenericTag{
        private static final String OPEN_TAG = "<document>";
        private static final String CLOSE_TAG = "</document>";
        //some tags

        public String xml;

        public Document (/*some params*/){
            xml = OPEN_TAG;
            //xml building
            xml += CLOSE_TAG;
        }
    @Override
    public String getXml() {
        return xml;
    }
    }
}

主要课程：

import java.util.Base64;

public class Main {

    public static void main(String[] args)
    {
        XmlBuilder.GenericTag[] arr = new XmlBuilder.GenericTag[2];
        arr[0] = new XmlBuilder.Authentication();
        arr[1] = new XmlBuilder.Document();
        byte[] foo= Base64.getDecoder().decode(XmlBuilder.generate(arr));
        System.out.println(new String(foo));
    }

}

Java：在最终类中实现接口的类

3 个答案: