android - 将三个json文件追加到一个json文件中

Question

目标:- 我必须将 3 个 json 文件合并为 1 个 json 文件。我需要在从输出文件中删除最后一个字符后将文本附加到输出文件。

注意:- 我这样做是为了将 3 个 json 文件合并到 1 个 json 文件中。我想将文本附加到输出文件中。这段代码附加了文本，但是不要删除最后一个 }。任何人都可以帮我处理代码。提前谢谢你，祝你有美好的一天。

我有一个 json 对象的记录，用于名称、电子邮件、纬度、经度、日期。这些字段位于不同的 json 文件中。我已将它们合并到 1 个 json 文件中。这项工作已完成。

预期输出:-当我追加下一条记录时，我希望 json 文件看起来像

{Record:[{"name1","val","date1","val","lat1","val"..}],[{"name2","val","date2","val","lat2","val"...}]}

实现的输出:-

{Record:[{"name1","val","date1","val","lat1","val"..}],{Record:[{"name2","val","date2","val","lat2","val"...}]}

代码:-

 static class CopyFileContent {

    public static void main(String[] args) {

        String root = Environment.getExternalStorageDirectory().toString(); //get access to directory path
        File myDir = new File(root + "/GeoPark");//create folder in internal storage
        myDir.mkdirs();// make directory
        File destFile = new File(myDir, FILENAME11);//making a new file in the folder
    /* Source file, from which content will be copied */
        File sourceFile1 = new File(myDir, FILENAME12);
        File sourceFile2 = new File(myDir, FILENAME13);
        File sourceFile3 = new File(myDir, FILENAME14);

    /* destination file, where the content to be pasted */
        // File destFile = new File(FILENAME);

    /* if file not exist then create one */
        if (!destFile.exists()) {
            try {
                destFile.createNewFile();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }

        InputStream input1 = null;
        InputStream input2 = null;
        InputStream input3 = null;
        OutputStream output = null;
        InputStream input4 = null;

        try {

            /* FileInputStream to read streams */
            input1 = new FileInputStream(sourceFile1);
            input2 = new FileInputStream(sourceFile2);
            input3 = new FileInputStream(sourceFile3);

        /* FileOutputStream to write streams */
            output = new FileOutputStream(destFile, true);

            byte[] buf = new byte[1024];
            int bytesRead;
            output.write("{Record:[{".getBytes());
            while ((bytesRead = input1.read(buf)) > 0) {
                output.write(buf, 1, bytesRead);

                RandomAccessFile f = new RandomAccessFile(destFile, "rw");
                long length = f.length() - 2;
                f.setLength(length);
                length = f.length();
                f.close();
                output.write(",".getBytes());

            }

            while ((bytesRead = input2.read(buf)) > 0) {
                output.write(buf, 1, bytesRead);
                RandomAccessFile f = new RandomAccessFile(destFile, "rw");
                long length = f.length() - 2;
                f.setLength(length);
                length = f.length();
                f.close();
                output.write(",".getBytes());

            }

            while ((bytesRead = input3.read(buf)) > 0) {
                output.write(buf, 1, bytesRead);
                RandomAccessFile f = new RandomAccessFile(destFile, "rw");
                long length = f.length() - 2;
                f.setLength(length);
                length = f.length();
                f.close();
                output.write(",".getBytes());
                output.write(b.getBytes());
                output.write(d.getBytes());
                output.write("}]}".getBytes());
                RandomAccessFile f1=new RandomAccessFile(destFile,"rw");
                long length1= f1.length()-1;
                f1.setLength(length1);
                f1.close();

                output.write(",".getBytes());
            }

        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {

                if (null != input1) {
                    input1.close();
                }

                if (null != input2) {
                    input2.close();
                }

                if (null != input3) {
                    input3.close();
                }

                if (null != output) {
                    output.close();
                }

            } catch (IOException e) {
                e.printStackTrace();
            }
        }

    }

}

Answer 1

在某些情况下，您需要深度合并，合并具有相同名称的字段的内容(就像在 Windows 中复制文件夹时一样)。此功能可能会有所帮助:

/**
 * Merge "source" into "target". If fields have equal name, merge them recursively.
 * @return the merged object (target).
 */
public static JSONObject deepMerge(JSONObject source, JSONObject target) throws JSONException {
    for (String key: JSONObject.getNames(source)) {
            Object value = source.get(key);
            if (!target.has(key)) {
                // new value for "key":
                target.put(key, value);
            } else {
                // existing value for "key" - recursively deep merge:
                if (value instanceof JSONObject) {
                    JSONObject valueJson = (JSONObject)value;
                    deepMerge(valueJson, target.getJSONObject(key));
                } else {
                    target.put(key, value);
                }
            }
    }
    return target;
}


public static void main(String[] args) throws JSONException {
    JSONObject a = new JSONObject("{offer: {issue1: value1}, accept: true}");
    JSONObject b = new JSONObject("{offer: {issue2: value2}, reject: false}");
    System.out.println(a+ " + " + b+" = "+JsonUtils.deepMerge(a,b));

}

如果你想合并它们，例如顶级对象有 4 个键(key1、Key2、Key3、Key4)，我认为您必须手动执行此操作:

JSONObject merged = new JSONObject(Obj1, JSONObject.getNames(Obj1));
for(String key : JSONObject.getNames(Obj2))
{
  merged.put(key, Obj2.get(key));
}