如何編寫一個潛在的巨大InputStream文件？

Question

我有一個API調用返回一個字節數組。我目前將結果串流到一個字節數組中，然後確保校驗和匹配，然後將ByteArrayOutputStream寫入File。代碼是這樣的，它工作得很好。

String path = "file.txt"; 
    ByteArrayOutputStream byteBuffer = new ByteArrayOutputStream(); 
    int bufferSize = 1024; 
    byte[] buffer = new byte[bufferSize]; 
    int len = 0; 
    while ((len = inputStream.read(buffer)) != -1) { 
     byteBuffer.write(buffer, 0, len); 
    } 
    FileOutputStream stream = new FileOutputStream(path); 
    stream.write(byteBuffer.toByteArray()); 

我關心我，從InputStream的結果可能會比Android的堆大小大，我能得到OutOfMemory異常如果整個字節數組是在內存中。將inputStream寫入塊中的最優雅的方式是什麼，這樣字節數組永遠不會超過堆大小？

Answer 1

我建議去跳過ByteArrayOutputStream並寫入到FileOutputStream中，這似乎爲解決我的顧慮。通過一次快速調整，FileOutputStream由BufferedOutputStream進行裝飾

String path = "file.txt"; 
OutputStream stream = new BufferedOutputStream(new FileOutputStream(path)); 
int bufferSize = 1024; 
byte[] buffer = new byte[bufferSize]; 
int len = 0; 
while ((len = is.read(buffer)) != -1) { 
    stream.write(buffer, 0, len); 
} 
if(stream!=null) 
    stream.close(); 

Answer 2

請勿寫信給ByteArrayOutputStream。直接寫入FileOutputStream。

String path = "file.txt"; 
FileOutputStream output = new FileOutputStream(path); 
int bufferSize = 1024; 
byte[] buffer = new byte[bufferSize]; 
int len = 0; 
while ((len = inputStream.read(buffer)) != -1) { 
    output.write(buffer, 0, len); 
}