我应该为“.thrift”文件定义什么样的服务,以便稍后将其用于我的程序?
此文件传输应位于客户端和服务器之间,它应该是“部分”。
StreamFileService.thrift:
struct FileChunk {
1: binary data
2: i64 remaining
}
service StreamFileService {
FileChunk getBytes(1:string fileName, 2: i64 offset, 3: i32 size);
}
StreamFileClient.java:
public class StreamFileClient {
private int fileChunkSize = 16;
private String filePath;
public String getFilePath() {
return filePath;
}
public void setFilePath(String filePath) {
this.filePath = filePath;
}
private void invoke() {
try {
TTransport theClientTransport = new TFramedTransport(new TSocket(
"127.0.0.1", 7911));
TProtocol theProtocol = new TBinaryProtocol(theClientTransport);
StreamFileService.Client theClient = new StreamFileService.Client(
theProtocol);
theClientTransport.open();
filePath = "/home/output/output.pdf";
File theFile2 = new File(filePath);
theFile2.createNewFile();
FileInputStream stream = new FileInputStream(theFile2);
long currentPosition = 0;
FileChannel theFileChannel = stream.getChannel();
boolean again = true;
do {
FileChunk chunk2 = theClient.getBytes(filePath,
currentPosition, fileChunkSize);
currentPosition += fileChunkSize;
theFileChannel.write(chunk2.data);
if (chunk2.remaining == 0)
again = false;
} while (again);
stream.close();
} catch (TTransportException e) {
e.printStackTrace();
} catch (TException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public static void main(String[] args) {
StreamFileClient theClient = new StreamFileClient();
theClient.invoke();
}
}
StreamFileServer.java:
public class StreamFileServer {
private void start() {
try {
TNonblockingServerTransport theServerSocket = new TNonblockingServerSocket(
7911);
StreamFileService.Processor theProcessor = new StreamFileService.Processor(
new StreamFileServiceImpl());
TServer theServer = new TNonblockingServer(
new TNonblockingServer.Args(theServerSocket)
.processor(theProcessor));
System.out.println("Server starting on port 7911...");
theServer.serve();
} catch (TTransportException e) {
e.printStackTrace();
}
}
public static void main(String[] args) {
StreamFileServer theFileServer = new StreamFileServer();
theFileServer.start();
}
}
StreamFileServiceImpl:
public class StreamFileServiceImpl implements StreamFileService.Iface {
public FileChunk getBytes(String filePath, long offset, int size)
throws TException {
File theFile = new File("/home/input/kl_12.pdf");
FileChunk chunk = new FileChunk();
try {
FileOutputStream stream = new FileOutputStream(theFile);
MappedByteBuffer buffer = stream.getChannel().map(
FileChannel.MapMode.READ_ONLY, offset, size);
chunk.data = buffer;
chunk.remaining = stream.getChannel().size() - offset - size;
stream.close();
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return chunk;
}
}
答案 0 :(得分:5)
您的代码对我来说并不是那么糟糕(未经过测试),并且没有太多变化。
怎么样
typedef binary binar
service StreamFileService {
binar getBytes(1:string fileName, 2: i64 offset, 3: i32 size);
i64 getSize(1:string fileName)
}
我还会返回一个包含字节的结构,但这或多或少是我的个人观点。
struct FileChunk {
1: binary data
2: i64 remaining
}
service StreamFileService {
FileChunk getBytes(1:string fileName, 2: i64 offset, 3: i32 size);
}
FileChunk
结构可以很容易地扩展,如果有必要,例如,为了返回额外的元数据,例如总大小(特别是如果大小随时间增长/缩小),剩余字节,关于数据格式的指示等。您不必这样做,因为如果以后需要这样做,您可以轻松扩展界面。味道很重要。