Question

我使用以下代码将ByteArray转换为String：

String sReturn = new String(byteArray, "UTF-8");

但是当ByteArray足够大时，我得到以下异常。

有没有其他方法可以将ByteArray转换为String而不会出现内存异常？

06-17 12:27:37.594: E/dalvikvm(1617): Out of memory: Heap Size=30663KB, Allocated=22087KB, Bitmap Size=936KB, Limit=32768KB
06-17 12:27:37.594: E/dalvikvm(1617): Extra info: Footprint=30663KB, Allowed Footprint=30663KB, Trimmed=616KB
06-17 12:27:37.594: W/dalvikvm(1617): threadid=9: thread exiting with uncaught exception (group=0x4001d648)
06-17 12:27:37.594: E/AndroidRuntime(1617): FATAL EXCEPTION: Thread-19
06-17 12:27:37.594: E/AndroidRuntime(1617): java.lang.OutOfMemoryError: (Heap Size=30663KB, Allocated=22087KB, Bitmap Size=936KB)
06-17 12:27:37.594: E/AndroidRuntime(1617):     at java.lang.String.<init>(String.java:422)
06-17 12:27:37.594: E/AndroidRuntime(1617):     at java.lang.String.<init>(String.java:276)
06-17 12:27:37.594: E/AndroidRuntime(1617):     at org.mabna.order.utils.Utilities.decompress(Utilities.java:389)
06-17 12:27:37.594: E/AndroidRuntime(1617):     at org.mabna.order.utils.WebserviceResponse.getClearedResponse(WebserviceResponse.java:18)
06-17 12:27:37.594: E/AndroidRuntime(1617):     at org.mabna.order.businessLayer.BoWebService.getDataForUpdate(BoWebService.java:216)
06-17 12:27:37.594: E/AndroidRuntime(1617):     at org.mabna.order.ui.ActToolDataExchange.threadGetDataForFullUpdate(ActToolDataExchange.java:389)
06-17 12:27:37.594: E/AndroidRuntime(1617):     at org.mabna.order.ui.ActToolDataExchange.access$9(ActToolDataExchange.java:380)
06-17 12:27:37.594: E/AndroidRuntime(1617):     at org.mabna.order.ui.ActToolDataExchange$35.run(ActToolDataExchange.java:639)
06-17 12:27:37.594: E/AndroidRuntime(1617):     at org.mabna.order.utils.Utilities$4.run(Utilities.java:924)

更新

public static String decompress(String zipText) throws IOException {
    byte[] compressed = Base64.decode(zipText);
    if (compressed.length > 4) {
        GZIPInputStream gzipInputStream = new GZIPInputStream(
                new ByteArrayInputStream(compressed, 4,
                        compressed.length - 4));

        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        for (int value = 0; value != -1;) {
            value = gzipInputStream.read();
            if (value != -1) {
                baos.write(value);
            }
        }
        gzipInputStream.close();
        baos.close();

        byte[] byteArray = baos.toByteArray();

        Log.i("toByteArray", String.valueOf(byteArray.length));

        String sReturn = new String(byteArray, "UTF-8");

        return sReturn;
    } else {
        return "";
    }
}



public static String decrypt(String encrypted, String password)
        throws Exception {

    byte[] encrypteddata = Base64.decode(encrypted);

    byte[] bytes = decrypt(encrypteddata, password);

    String result = new String(bytes, "UTF-8");

    return result;
}

public static byte[] decrypt(byte[] encrypted, String password)
        throws Exception {

    byte[] passwordKey = encodeDigest(password);
    try {
        aesCipher = Cipher.getInstance(CIPHER_TRANSFORMATION);
    } catch (NoSuchAlgorithmException e) {
        throw new Exception(
                "Decryption Exception: No such algorithm\r\n" + e
                        .toString());
    } catch (NoSuchPaddingException e) {
        throw new Exception(
                "Decryption Exception: No such padding PKCS5\r\n" + e
                        .toString());
    }
    secretKey = new SecretKeySpec(passwordKey, CIPHER_ALGORITHM);

    try {
        aesCipher.init(Cipher.DECRYPT_MODE, secretKey, ivParameterSpec);
    } catch (InvalidKeyException e) {
        throw new Exception(
                "Decryption Exception: Invalid key\r\n" + e.toString());
    } catch (InvalidAlgorithmParameterException e) {
        throw new Exception(
                "Decryption Exception: Invalid algorithm\r\n" + e
                        .toString());
    }

    byte[] encryptedData;
    try {
        encryptedData = aesCipher.doFinal(encrypted);
    } catch (IllegalBlockSizeException e) {
        throw new Exception(
                "Decryption Exception: Illegal block size\r\n" + e
                        .toString());
    } catch (BadPaddingException e) {
        throw new Exception(
                "Decryption Exception: Bad padding\r\n" + e
                        .toString());
    }
    return encryptedData;
}

Answer 1

以下代码段将帮助您。尝试阅读块

             StringBuilder sb=new StringBuilder();  

             Log.v("abc","length : " + byteArray.length);  

             while (totalBytesRead < formDataLength) {    
                 byteRead = in.read(dataBytes, totalBytesRead, formDataLength);    
                 // byteRead = in.read(dataBytes);    
                 //totalBytesRead += byteRead;    
                 sb.append((char)byteRead);  
             }    

              String s=sb.toString();

Answer 2

我会一次将其分解为1000个字符串。 3663125字节是很多内存，特别是对于android。

ArrayList<String> strings = new ArrayList<String>();
byte[] set = new byte[1000];
for(int x = 0, index = 0; x < byteArray.length;x++, index++)
{
    set[index] = byteArray[x];
    if(index == 999)
    {
        strings.add(new String(set, "Unicode"));
        index = 0;
        if(byteArray.length - x < 1000) // shorten the set when there are less than 1000 bytes left
            set = new byte[byteArray.length - x];
   }
}

strings.add(new String(set, "Unicode"));

String stringArray[] = (String[])strings.toArray();

这会为你分解，你可以将1000改为你想要的任何东西，如果它太小了。

Answer 3

你正在过度分配内存 - 首先你解压缩base 64并为此分配缓冲区，然后你解压缩它并将chusnks写入BAOS（这是一个alocating并重新分配内存块）然后你再次将它复制到字符串 - no想知道它耗尽内存。

尝试将此内容重写为流式处理（有srteaming base64 dcoding，以及gzip解码器）

将ByteArray转换为String时出现OutOfMemory异常？

3 个答案: