Module de.haumacher.msgbuf

Package de.haumacher.msgbuf.binary

Interface DataReader

All Known Implementing Classes:

OctetDataReader

public interface DataReader

Input interface for reading binary messages into data objects.

A message constructed by a DataWriter may only contain object at top-level. Therefore the first call to an instance of DataReader must be beginObject().

See Also:

• DataWriter

Method Summary

Modifier and Type	Method	Description
int	beginArray()	Starts reading an array.
void	beginObject()	Starts reading an object.
void	endArray()	Finishes reading the array started with beginArray().
void	endObject()	Finishes reading the object started with the last call to beginObject().
boolean	hasNext()	When reading an object or array, whether there are more fields or array elements left to read.
byte[]	nextBinary()	Reads a binary string value.
InputStream	nextBinaryStream()	Reads a binary stream value.
default boolean	nextBoolean()	Reads a boolean value.
double	nextDouble()	Reads a 64 bit double value.
float	nextFloat()	Reads a 32 bit float value.
int	nextInt()	Reads an (unsigned) integer value.
int	nextIntFixed()	Reads a full 32 bit integer value.
int	nextIntSigned()	Reads a signed integer value.
long	nextLong()	Reads an (unsigned) long value.
long	nextLongFixed()	Reads a full 64 bit long value.
long	nextLongSigned()	Reads a signed long value.
int	nextName()	When reading an object, retrieves the next field identifier.
String	nextString()	Reads an utf-8 String value.
void	skipValue()	Skips the current value to read.

Method Details

beginObject

void beginObject()
          throws IOException

Starts reading an object.

After this call, an alternating sequence of calls to nextName() followed by a value retrieval method such as nextInt(),... nextString() followed by a final call to endObject() is expected.

Throws:

IOException - If reading fails.

endObject

void endObject()
        throws IOException

Finishes reading the object started with the last call to beginObject().

Throws:

IOException - If reading fails.

hasNext

boolean hasNext()
         throws IOException

When reading an object or array, whether there are more fields or array elements left to read.

Returns:

The retrieved value.

Throws:

IOException - If reading fails.

nextName

int nextName()
      throws IOException

When reading an object, retrieves the next field identifier.

Note: hasNext() must return true to be able to read the next field identifier.

Returns:

The retrieved value.

Throws:

IOException - If reading fails.

nextBoolean

default boolean nextBoolean()
                     throws IOException

Reads a boolean value.

Returns:

The retrieved value.

Throws:

IOException - If reading fails.

nextInt

int nextInt()
     throws IOException

Reads an (unsigned) integer value.

Returns:

The retrieved value.

Throws:

IOException - If reading fails.

nextIntSigned

int nextIntSigned()
           throws IOException

Reads a signed integer value.

Returns:

The retrieved value.

Throws:

IOException - If reading fails.

nextIntFixed

int nextIntFixed()
          throws IOException

Reads a full 32 bit integer value.

Returns:

The retrieved value.

Throws:

IOException - If reading fails.

nextLong

long nextLong()
       throws IOException

Reads an (unsigned) long value.

Returns:

The retrieved value.

Throws:

IOException - If reading fails.

nextLongSigned

long nextLongSigned()
             throws IOException

Reads a signed long value.

Returns:

The retrieved value.

Throws:

IOException - If reading fails.

nextLongFixed

long nextLongFixed()
            throws IOException

Reads a full 64 bit long value.

Returns:

The retrieved value.

Throws:

IOException - If reading fails.

nextFloat

float nextFloat()
         throws IOException

Reads a 32 bit float value.

Returns:

The retrieved value.

Throws:

IOException - If reading fails.

nextDouble

double nextDouble()
           throws IOException

Reads a 64 bit double value.

Returns:

The retrieved value.

Throws:

IOException - If reading fails.

nextString

String nextString()
           throws IOException

Reads an utf-8 String value.

Returns:

The retrieved value.

Throws:

IOException - If reading fails.

nextBinary

byte[] nextBinary()
           throws IOException

Reads a binary string value.

The value might have been produced by DataWriter.value(byte[]), or DataWriter.valueBinaryStream(). Best efficiency is achieved, if a value produced with DataWriter.valueBinaryStream() is read by nextBinaryStream().

Returns:

The retrieved value.

Throws:

IOException - If reading fails.

nextBinaryStream

InputStream nextBinaryStream()
                      throws IOException

Reads a binary stream value.

The value might have been produced by DataWriter.value(byte[]), or DataWriter.valueBinaryStream(). Best efficiency is achieved, if a value produced with DataWriter.valueBinaryStream() is read by nextBinaryStream().

Returns:

The retrieved value as stream.

Throws:

IOException - If reading fails.

beginArray

int beginArray()
        throws IOException

Starts reading an array.

Returns:

The number of array elements to read.

Throws:

IOException - If reading fails.

endArray

void endArray()
       throws IOException

Finishes reading the array started with beginArray().

Throws:

IOException - If reading fails.

skipValue

void skipValue()
        throws IOException

Skips the current value to read.

Throws:

IOException - If reading fails.