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循环中的Java缓冲读取器

我试图创建一个JAVA程序,从txt文件中读取一些标记,并创建将这些标记作为字段的对象。我正在发布我有问题的代码部分:

try{
        line = reader.readLine();
        while(line != null){
            if (!line.trim().equals(" ") && line.trim().equals("ITEM_LIST")) {
                    line = reader.readLine();
                    if (line != null && line.trim().equals("{"))) {
                            line = reader.readLine();
                            if (line != null) {
                                if (line.trim().equals("ITEM")) {
                                    line = reader.readLine();
                                    if (line != null) {
                                        if (line.trim().equals("{")) {
                                            if (line != null) {
                                                line = reader.readLine();
                                                while (!((line.trim().startsWith("ITEM_TYPE ")) {
                                                    line = reader.readLine();
                                                    if((line.trim().startsWith("ITEM_TYPE ")){
                                                        String devType = line.trim().substring(10);
                                                    }
                                                )
                                                if(devType.toLowerCase() == "tv"){
                                                    dev = new TV();
                                                    line = reader.readLine();
                                                    if (line != null){
                                                        if (line.trim().toUpperCase().startsWith("CODE ")) {
                                                            dev.setCode(line.substring(5).trim());
                                                        }
                                                    }

                                                    line = reader.readLine();
                                                    if (line != null){
                                                        if (line.trim().toUpperCase().startsWith("MODEL ")) {
                                                            dev.setModelName(line.substring(6).trim());
                                                        }
                                                    }

                                                    line = reader.readLine();
                                                    if (line != null){
                                                        if (line.trim().toUpperCase().startsWith("MODEL_YEAR ")) {
                                                            dev.setYear(line.substring(11).trim());
                                                        }
                                                    }

                                                    line = reader.readLine();
                                                    if (line != null){
                                                        if (line.trim().toUpperCase().startsWith("MANUFACTURER ")) {
                                                            dev.setConstructor(line.substring(13).trim());
                                                        }
                                                    }

                                                    line = reader.readLine();
                                                    if (line != null){
                                                        if (line.trim().toUpperCase().startsWith("PRICE ")) {
                                                            dev.setPrice(Double.parseDouble(line.substring(6).trim()));
                                                        }
                                                    }

                                                    line = reader.readLine();
                                                    if (line != null){
                                                        if (line.trim().toUpperCase().startsWith("PANEL_TYPE ")) {
                                                            dev.setType(line.substring(11).trim());
                                                        }
                                                    }

                                                    line = reader.readLine();
                                                    if (line != null){
                                                        if (line.trim().toUpperCase().startsWith("DIMENSIONS ")) {
                                                            dev.setSize(line.substring(11).trim());
                                                        }
                                                    }

                                                    line = reader.readLine();
                                                    if (line != null){
                                                        if (line.trim().toUpperCase().startsWith("RESOLUTION ")) {
                                                            dev.setResolution(line.substring(10).trim());
                                                        }
                                                    }

                                                    line = reader.readLine();
                                                    if (line != null){
                                                        if (line.trim().toUpperCase().startsWith("INTERFACES ")) {
                                                            dev.setPorts(line.substring(10).trim());
                                                        }
                                                    }

                                                    line = reader.readLine();
                                                    if (line != null){
                                                        if (line.trim().toUpperCase().startsWith("PIECES ")) {
                                                            dev.setPieces(line.substring(7).trim());
                                                        }
                                                    }

我的问题是如何修改代码,以便首先读取标记ITEM_TYPE,然后创建特定项目(例如tv),然后读取所有其他标记并完成对象。txt文件中标记的顺序不是特定的,如果缺少标记,该字段将采用默认值。以下是txt文件:

  ITEM_LIST
{
ITEM
{
    CODE ADLS443
    ITEM_TYPE tv
    MODEL IDL32KJX4300
    MODEL_YEAR 2016
    MANUFACTURER Samsung
    PRICE 350
    PANEL_TYPE LCD
    DIMENSIONS 32
    RESOLUTION "Full HD"
    INTERFACES "HDMI USB SCART"
    PIECES 43
}
ITEM
{
    CODE KD444211
    ITEM_TYPE tv
    MODEL KDL49DDR4600
    MODEL_YEAR 2014
    MANUFACTURER Sony
    PRICE 600
    PANEL_TYPE LED
    DIMENSIONS 49
    RESOLUTION "Ultra HD"
    INTERFACES "HDMI USB SCART Ethernet WiFi"
    PIECES 8
}
ITEM
{
    CODE 2445DBS41
    ITEM_TYPE blueray
    MODEL JVX44R32
    MODEL_YEAR 2012
    MANUFACTURER LG
    PRICE 250
    RESOLUTION 1080p
    FORMAT BR-W
    PIECES 12
}

如果缺少有关代码的任何信息,我很抱歉


共 (1) 个答案

  1. # 1 楼答案

    简短的回答——你不能

    更好的答案-阅读ITEM下的所有内容,提取ITEM_TYPE,创建所需的对象并用其余数据填充它

    另外,您可能只想在执行reader.readLine()之后执行line.trim()一次,并且通常将代码重写为状态机,这样就不会有那么高级别的嵌套if