com.liulishuo.filedownloader.connection

Interface FileDownloadConnection

All Known Implementing Classes:

FileDownloadUrlConnection

public interface FileDownloadConnection

The connection used for connecting to the network.

Field Summary

Fields

Modifier and Type	Field and Description
static int	NO_RESPONSE_CODE
static int	RESPONSE_CODE_FROM_OFFSET

Method Summary

Modifier and Type	Method and Description
void	addHeader(String name, String value) Sets the header named name to value.
boolean	dispatchAddResumeOffset(String etag, long offset) If we find the file has been downloaded several bytes, we will try to resume from the breakpoint from offset length.
void	ending() To Be Reused or Close this connection, since this connection is ending in this session.
void	execute() Invokes the request immediately, and blocks until the response can be processed or is in error.
InputStream	getInputStream() Returns an input stream that reads from this open connection.
Map<String,List<String>>	getRequestHeaderFields() Returns an unmodifiable Map of general request header fields for this connection.
int	getResponseCode() Gets the status code from an HTTP response message.
String	getResponseHeaderField(String name) Returns the value of the named header field, which would be the response-header field.
Map<String,List<String>>	getResponseHeaderFields() Returns an unmodifiable Map of the header fields.
boolean	setRequestMethod(String method) Set the method for the request, one of: GET POST HEAD OPTIONS PUT DELETE TRACE are legal, subject to protocol restrictions.

Field Detail

NO_RESPONSE_CODE

static final int NO_RESPONSE_CODE

See Also:

Constant Field Values

RESPONSE_CODE_FROM_OFFSET

static final int RESPONSE_CODE_FROM_OFFSET

See Also:

Constant Field Values

Method Detail

addHeader

void addHeader(String name,
               String value)

Sets the header named name to value.

The capacity of this method is similar to the URLConnection.addRequestProperty(String, String)

dispatchAddResumeOffset

boolean dispatchAddResumeOffset(String etag,
                                long offset)

If we find the file has been downloaded several bytes, we will try to resume from the breakpoint from offset length.

Parameters:

etag - the etag is stored by the past downloaded.

offset - the offset length has already been downloaded.

Returns:

true if adding resume offset was dispatched, so we can't handle that by internal.

getInputStream

InputStream getInputStream()
                    throws IOException

Returns an input stream that reads from this open connection.

The capacity of this method is similar to the URLConnection.getInputStream()

Returns:

an input stream that reads from this open connection.

Throws:

IOException

getRequestHeaderFields

Map<String,List<String>> getRequestHeaderFields()

Returns an unmodifiable Map of general request header fields for this connection. The Map keys are Strings that represent the request-header field names. Each Map value is a unmodifiable List of Strings that represents the corresponding field values.

The capacity of this method is similar to the URLConnection.getRequestProperties()

Returns:

a Map of the general request properties for this connection.

getResponseHeaderFields

Map<String,List<String>> getResponseHeaderFields()

Returns an unmodifiable Map of the header fields. The Map keys are Strings that represent the response-header field names. Each Map value is an unmodifiable List of Strings that represents the corresponding field values.

The capacity of this method is similar to the URLConnection.getHeaderFields()

Returns:

a Map of header fields

getResponseHeaderField

String getResponseHeaderField(String name)

Returns the value of the named header field, which would be the response-header field.

If called on a connection that sets the same header multiple times with possibly different values, only the last value is returned.

Parameters:

name - the name of a header field.

Returns:

the value of the named header field, or null if there is no such field in the header.

setRequestMethod

boolean setRequestMethod(String method)
                  throws ProtocolException

Set the method for the request, one of:

• GET
• POST
• HEAD
• OPTIONS
• PUT
• DELETE
• TRACE

are legal, subject to protocol restrictions. The default method is GET.

Parameters:

method - the HTTP method

Returns:

true if set effect, otherwise false.

Throws:

ProtocolException - if the method cannot be reset or if the requested method isn't valid for HTTP.

SecurityException - if a security manager is set and the method is "TRACE", but the "allowHttpTrace" NetPermission is not granted.

execute

void execute()
      throws IOException

Invokes the request immediately, and blocks until the response can be processed or is in error.

Throws:

IOException

getResponseCode

int getResponseCode()
             throws IOException

Gets the status code from an HTTP response message.

If this is not http/https protocol connection: 1. If you make sure this connection is resume from the offset breakpoint(which you can check out this through dispatchAddResumeOffset(String, long)), please return RESPONSE_CODE_FROM_OFFSET 2. otherwise, return NO_RESPONSE_CODE.

Returns:

the HTTP Status-Code, or -1

Throws:

IOException

ending

void ending()

To Be Reused or Close this connection, since this connection is ending in this session.