Android - 从Web服务反序列化大型Json字符串（java.lang.OutOfMemoryError）

Question

首先，我应该提一下，我已经看到其他人提出的有关此错误的其他问题，但我无法获得线索。

我正在为我的应用制作照片库，照片以字节形式插入网站数据库。我准备了一个Web服务，它将这些图片作为json字符串返回。一切都很好，直到网站数据库中的照片数量变高（返回的json字符串变得越来越大）

当我试图读取这个json并将其放入字符串时，我收到此错误：

java.lang.RuntimeException: An error occured while executing doInBackground()
            at android.os.AsyncTask$3.done(AsyncTask.java:300)
            at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:355)
            at java.util.concurrent.FutureTask.setException(FutureTask.java:222)
            at java.util.concurrent.FutureTask.run(FutureTask.java:242)
            at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231)
            at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
            at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
            at java.lang.Thread.run(Thread.java:841)
     Caused by: java.lang.OutOfMemoryError
            at java.lang.AbstractStringBuilder.enlargeBuffer(AbstractStringBuilder.java:94)
            at java.lang.AbstractStringBuilder.append0(AbstractStringBuilder.java:124)
            at java.lang.StringBuilder.append(StringBuilder.java:271)
            at org.kxml2.io.KXmlParser.readValue(KXmlParser.java:1345)
            at org.kxml2.io.KXmlParser.next(KXmlParser.java:390)
            at org.kxml2.io.KXmlParser.next(KXmlParser.java:310)
            at org.ksoap2.serialization.SoapSerializationEnvelope.readUnknown(SoapSerializationEnvelope.java:210)
            at org.ksoap2.serialization.SoapSerializationEnvelope.read(SoapSerializationEnvelope.java:366)
            at org.ksoap2.serialization.SoapSerializationEnvelope.readUnknown(SoapSerializationEnvelope.java:233)
            at org.ksoap2.serialization.SoapSerializationEnvelope.read(SoapSerializationEnvelope.java:366)
            at org.ksoap2.serialization.SoapSerializationEnvelope.parseBody(SoapSerializationEnvelope.java:121)
            at org.ksoap2.SoapEnvelope.parse(SoapEnvelope.java:137)
            at org.ksoap2.transport.Transport.parseResponse(Transport.java:63)
            at org.ksoap2.transport.HttpTransportSE.call(HttpTransportSE.java:100)
            at ir.pargansystem.orkidehtalaei.OrkidehWebService.Call(OrkidehWebService.java:42)
            at ir.pargansystem.orkidehtalaei.photogallery.PhotoGalleryViewPager$GetDataTask.doInBackground(PhotoGalleryViewPager.java:226)
            at ir.pargansystem.orkidehtalaei.photogallery.PhotoGalleryViewPager$GetDataTask.doInBackground(PhotoGalleryViewPager.java:218)
            at android.os.AsyncTask$2.call(AsyncTask.java:288)
            at java.util.concurrent.FutureTask.run(FutureTask.java:237)
            at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231)
            at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
            at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
            at java.lang.Thread.run(Thread.java:841)

如何在不出现内存错误的情况下读取json并对其进行反序列化？ 任何帮助，将不胜感激！

编辑1： 网络服务代码：

public String Call(String methodName) {
        String loginUser = "user";
        String loginPassword = "pass";

        SoapObject request = new SoapObject(WSDL_TARGET_NAMESPACE, methodName);
        PropertyInfo pi = new PropertyInfo();
        pi.setName("username");
        pi.setValue(loginUser);
        pi.setType(String.class);
        request.addProperty(pi);
        pi = new PropertyInfo();
        pi.setName("password");
        pi.setValue(loginPassword);
        pi.setType(String.class);
        request.addProperty(pi);

        SoapSerializationEnvelope envelope = new SoapSerializationEnvelope(
                SoapEnvelope.VER11);
        envelope.dotNet = true;

        envelope.setOutputSoapObject(request);

        HttpTransportSE httpTransport = new HttpTransportSE(SOAP_ADDRESS);
        Object response = null;
        try {
            httpTransport.call(SOAP_ACTION + methodName, envelope);
            response = envelope.getResponse();
        } catch (Exception exception) {
            response = exception.toString();
            exception.printStackTrace();
        }
        return response.toString();
    }

并在此处调用网络服务：

private class GetDataTask extends AsyncTask<Void, Void, Void> {
        String jsonString;

        @Override
        protected Void doInBackground(Void... params) {
            // Simulates a background job.
            try {
            OrkidehWebService fws = new OrkidehWebService();
            jsonString = fws.Call("getGalleryData"); // I get the error here

            } catch (Exception e) {
                e.printStackTrace();
            }
            return null;
        }
@Override
    protected void onPostExecute(Void result) {
        try {
            Gson gson = new Gson();
            @SuppressWarnings("serial")
            Type collectionType = new TypeToken<List<PhotoGalleryEntity>>() {
            }.getType();

            lstPhotos = gson.fromJson(jsonString, collectionType);

            Collections.sort(lstPhotos, new Comparator<PhotoGalleryEntity>() {
                public int compare(PhotoGalleryEntity o1, PhotoGalleryEntity o2) {
                    return o1.getPriority() - o2.getPriority();
                }
            });
}