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/*
* Copyright (c) 2000, 2021, Oracle and/or its affiliates.
*
* Licensed under the Universal Permissive License v 1.0 as shown at
* http://oss.oracle.com/licenses/upl.
*/
package com.tangosol.io;
import com.tangosol.util.ExternalizableHelper;
import java.io.DataInput;
import java.io.DataOutput;
import java.io.EOFException;
import java.io.IOException;
import java.io.OutputStream;
import java.nio.ByteBuffer;
import com.tangosol.util.Binary;
import com.tangosol.util.ByteSequence;
/**
* The ReadBuffer interface represents an in-memory block of binary data,
* such as that represented by a byte[], a Binary object, or an NIO buffer.
*
* @author cp 2005.01.18
*/
public interface ReadBuffer
extends ByteSequence, Cloneable
{
/**
* Determine the length of the buffer.
*
* @return the number of bytes of data represented by this ReadBuffer
*/
public int length();
/**
* Returns the byte at the specified offset. An offset ranges
* from 0 to length() - 1. The first byte
* of the sequence is at offset 0, the next at offset
* 1, and so on, as for array indexing.
*
* @param of the offset (index) of the byte
*
* @return the byte at the specified offset in this ReadBuffer
*
* @exception IndexOutOfBoundsException if the of
* argument is negative or not less than the length of this
* ReadBuffer
*/
public byte byteAt(int of);
/**
* Copies bytes from this ReadBuffer into the destination byte array.
*
* The first byte to be copied is at offset ofBegin;
* the last byte to be copied is at offset ofEnd-1
* (thus the total number of bytes to be copied is ofEnd -
* ofBegin). The bytes are copied into the sub-array of
* abDest starting at offset ofDest
* and ending at index:
*
* ofDest + (ofEnd - ofBegin) - 1
*
*
* This method is the ReadBuffer equivalent of
* {@link String#getChars(int, int, char[], int)}. It allows the caller
* to extract a chunk of bytes into the caller's own array.
*
* @param ofBegin offset of the first byte in the ReadBuffer to copy
* @param ofEnd offset after the last byte in the ReadBuffer to copy
* @param abDest the destination byte array
* @param ofDest the offset in the destination byte array to copy the
* first byte to
*
* @exception IndexOutOfBoundsException Thrown if any of the following
* is true:
*
* ofBegin is negative;
* ofBegin is greater than ofEnd
* ofEnd is greater than the length of this
* ReadBuffer;
* ofDest is negative
* ofDest + (ofEnd - ofBegin) is larger than
* abDest.length
*
* @exception NullPointerException if abDest is
* null
*/
public void copyBytes(int ofBegin, int ofEnd, byte abDest[], int ofDest);
/**
* Get a BufferInput object to read data from this buffer. Note that each
* call to this method will return a new BufferInput object, with the
* possible exception being that a zero-length ReadBuffer could always
* return the same instance (since there is nothing to read).
*
* @return a BufferInput that is reading from this buffer starting at
* offset zero
*/
public BufferInput getBufferInput();
/**
* Obtain a ReadBuffer for a portion of this ReadBuffer.
*
* @param of the beginning index, inclusive
* @param cb the number of bytes to include in the resulting ReadBuffer
*
* @return a ReadBuffer that represents a portion of this ReadBuffer
*
* @exception IndexOutOfBoundsException if of or
* cb is negative, or of + cb is
* larger than the length of this ReadBuffer
* object
*/
public ReadBuffer getReadBuffer(int of, int cb);
/**
* Write the contents of this ReadBuffer to an OutputStream.
*
* @param out an OutputStream to write to
*
* @throws IOException if an I/O exception occurs
*/
public void writeTo(OutputStream out) throws IOException;
/**
* Write the contents of the ReadBuffer to an OutputStream.
*
* @param out an OutputStream to write to
* @param of the beginning index, inclusive
* @param cb the number of bytes to write to an OutputStream
*
* @throws IOException if an I/O exception occurs
*/
public void writeTo(OutputStream out, int of, int cb) throws IOException;
/**
* Write the contents of this ReadBuffer to a DataOutput.
*
* @param out a DataOutput to write to
*
* @throws IOException if an I/O exception occurs
*/
public void writeTo(DataOutput out) throws IOException;
/**
* Write the contents of this ReadBuffer to a DataOutput.
*
* @param out a DataOutput to write to
* @param of the beginning index, inclusive
* @param cb the number of bytes to write to a DataOutput
*
* @throws IOException if an I/O exception occurs
*/
public void writeTo(DataOutput out, int of, int cb) throws IOException;
/**
* Write the contents of the Binary object to a ByteBuffer.
*
* @param buf a ByteBuffer to write to
*/
public void writeTo(ByteBuffer buf);
/**
* Write the contents of the Binary object to a ByteBuffer.
*
* @param buf an ByteBuffer to write to
* @param of the beginning index, inclusive
* @param cb the number of bytes to write to a ByteBuffer
*
* @throws IOException if an I/O exception occurs
*/
public void writeTo(ByteBuffer buf, int of, int cb) throws IOException;
/**
* Get the contents of the ReadBuffer as a byte array.
*
* This is the equivalent of toByteArray(0, length()).
*
* @return a byte[] with the contents of this ReadBuffer object
*/
public byte[] toByteArray();
/**
* Get a portion of the contents of the ReadBuffer as a byte array.
*
* This method is an equivalent of
* getReadBuffer(of, cb).toByteArray().
*
* @param of the beginning index, inclusive
* @param cb the number of bytes to include in the resulting byte[]
*
* @return a byte[] containing the specified portion of this ReadBuffer
*
* @exception IndexOutOfBoundsException if of or
* cb is negative, or of + cb is
* larger than the length of this ReadBuffer
* object
*/
public byte[] toByteArray(int of, int cb);
/**
* Return a new Binary object that holds the complete contents of this
* ReadBuffer.
*
* This is the equivalent of toBinary(0, length()).
*
* @return the contents of this ReadBuffer as a Binary object
*/
public Binary toBinary();
/**
* Return a Binary object that holds the specified portion of this
* ReadBuffer.
*
* This method is an equivalent of
* getReadBuffer(of, cb).toBinary().
*
* @param of the beginning index, inclusive
* @param cb the number of bytes to include in the Binary object
*
* @return a Binary object containing the specified portion of this
* ReadBuffer
*
* @exception IndexOutOfBoundsException if of or
* cb is negative, or of + cb is
* larger than the length of this ReadBuffer
* object
*/
public Binary toBinary(int of, int cb);
/**
* Return a read-only ByteBuffer view of this ReadBuffer. This view may or
* may not reflect any subsequent changes made to the underlying content.
*
* @return a read-only ByteBuffer view of this ReadBuffer
*
* @since Coherence 12.1.2
*/
public ByteBuffer toByteBuffer();
/**
* Return a read-only ByteBuffer view of the specified portion of this
* ReadBuffer. This view may or may not reflect any subsequent changes made
* to the underlying content.
*
* This method is an equivalent of
* getReadBuffer(of, cb).toByteBuffer().
*
* @param of the beginning index, inclusive
* @param cb the number of bytes to include in the ByteBuffer object
*
* @return a read-only ByteBuffer view of the specified portion of this
* ReadBuffer
*
* @exception IndexOutOfBoundsException if of or
* cb is negative, or of + cb is
* larger than the length of this ReadBuffer object
*
* @since Coherence 12.1.2
*/
public ByteBuffer toByteBuffer(int of, int cb);
/**
* {@inheritDoc}
*
* @since Coherence 3.7
*/
public ByteSequence subSequence(int ofStart, int ofEnd);
// ----- Object methods -------------------------------------------------
/**
* Compare two ReadBuffer objects for equality.
*
* @param o a ReadBuffer object
*
* @return true iff the other ReadBuffer is identical to this
*/
public boolean equals(Object o);
/**
* Create a clone of this ReadBuffer object.
*
* @return a ReadBuffer object with the same contents as this
* ReadBuffer object
*/
public Object clone();
// ----- inner interface: BufferInput -----------------------------------
/**
* The BufferInput interface represents a DataInputStream on top of a
* ReadBuffer.
*
* @author cp 2005.01.18
*/
public interface BufferInput
extends InputStreaming, DataInput
{
// ----- InputStreaming methods ---------------------------------
/**
* Returns the number of bytes that can be read (or skipped over) from
* this input stream without causing a blocking I/O condition to
* occur. This method reflects the assumed implementation of various
* buffering InputStreams, which can guarantee non-blocking reads up
* to the extent of their buffers, but beyond that the read operations
* will have to read from some underlying (and potentially blocking)
* source.
*
* BufferInput implementations must implement this method to return
* the extent of the buffer that has not yet been read; in other
* words, the entire un-read portion of the buffer must be
* available.
*
* @return the number of bytes that can be read from this InputStream
* without blocking
*
* @exception IOException if an I/O error occurs
*/
public int available()
throws IOException;
/**
* Close the InputStream and release any system resources associated
* with it.
*
* BufferInput implementations do not pass this call down onto an
* underlying stream, if any.
*
* @exception IOException if an I/O error occurs
*/
public void close()
throws IOException;
/**
* Marks the current read position in the InputStream in order to
* support the stream to be later "rewound" (using the {@link #reset}
* method) to the current position. The caller passes in the maximum
* number of bytes that it expects to read before calling the
* {@link #reset} method, thus indicating the upper bounds of the
* responsibility of the stream to be able to buffer what it has read
* in order to support this functionality.
*
* BufferInput implementations ignore the cbReadLimit;
* they must support an unlimited read limit, since they appear to the
* user as an input stream on top of a fully realized read buffer.
*
* @param cbReadLimit the maximum number of bytes that caller expects
* the InputStream to be able to read before the
* mark position becomes invalid
*/
public void mark(int cbReadLimit);
/**
* Determine if this InputStream supports the {@link #mark} and
* {@link #reset} methods.
*
* BufferInput implementations must support the {@link #mark}
* and {@link #reset} methods, so this method always returns
* true.
*
* @return true if this InputStream supports the mark
* and reset method; false otherwise
*/
public boolean markSupported();
// ----- DataInput methods --------------------------------------
/**
* Read ab.length bytes and store them in
* ab.
*
* This method blocks until input data is available, the end of the
* stream is detected, or an exception is thrown.
*
* @param ab the array to store the bytes which are read from the
* stream
*
* @exception NullPointerException if the passed array is null
* @exception java.io.EOFException if the stream is exhausted before the
* number
* of bytes indicated by the array length could be read
* @exception IOException if an I/O error occurs
*/
public void readFully(byte ab[])
throws IOException;
/**
* Read cb bytes and store them in ab
* starting at offset of.
*
* This method blocks until input data is available, the end of the
* stream is detected, or an exception is thrown.
*
* @param ab the array to store the bytes which are read from the
* stream
* @param of the offset into the array that the read bytes will be
* stored
* @param cb the maximum number of bytes to read
*
* @exception NullPointerException if the passed array is null
* @exception IndexOutOfBoundsException if of or
* cb is negative, or of+cb is
* greater than the length of the ab
* @exception java.io.EOFException if the stream is exhausted before the
* number of bytes indicated by the array length could be
* read
* @exception IOException if an I/O error occurs
*/
public void readFully(byte ab[], int of, int cb)
throws IOException;
/**
* Skips over up to the specified number of bytes of data. The number
* of bytes actually skipped over may be fewer than the number
* specified to skip, and may even be zero; this can be caused by an
* end-of-file condition, but can also occur even when there is data
* remaining to be read. As a result, the caller should check the
* return value from this method, which indicates the actual number of
* bytes skipped.
*
* @param cb the maximum number of bytes to skip over
*
* @return the actual number of bytes that were skipped over
*
* @exception IOException if an I/O error occurs
*/
public int skipBytes(int cb)
throws IOException;
/**
* Read a boolean value.
*
* This method is the counterpart for the
* {@link java.io.DataOutput#writeBoolean} method.
*
* @return either true or false
*
* @exception EOFException if the value could not be read because no
* more data remains to be read
* @exception IOException if an I/O error occurs
*/
public boolean readBoolean()
throws IOException;
/**
* Read a byte value.
*
* This method is the counterpart for the
* {@link java.io.DataOutput#writeByte} method.
*
* @return a byte value
*
* @exception EOFException if the value could not be read because no
* more data remains to be read
* @exception IOException if an I/O error occurs
*/
public byte readByte()
throws IOException;
/**
* Read an unsigned byte value.
*
* This method is the counterpart for the
* {@link java.io.DataOutput#writeByte} method when it is used with
* unsigned 8-bit values.
*
* @return an int value in the range 0x00 to 0xFF
*
* @exception EOFException if the value could not be read because no
* more data remains to be read
* @exception IOException if an I/O error occurs
*/
public int readUnsignedByte()
throws IOException;
/**
* Read a short value.
*
* This method is the counterpart for the
* {@link java.io.DataOutput#writeShort} method.
*
* @return a short value
*
* @exception EOFException if the value could not be read because no
* more data remains to be read
* @exception IOException if an I/O error occurs
*/
public short readShort()
throws IOException;
/**
* Read an unsigned short value.
*
* This method is the counterpart for the
* {@link java.io.DataOutput#writeShort} method when it is used with
* unsigned 16-bit values.
*
* @return an int value in the range of 0x0000 to 0xFFFF
*
* @exception EOFException if the value could not be read because no
* more data remains to be read
* @exception IOException if an I/O error occurs
*/
public int readUnsignedShort()
throws IOException;
/**
* Read a char value.
*
* This method is the counterpart for the
* {@link java.io.DataOutput#writeChar} method.
*
* @return a char value
*
* @exception EOFException if the value could not be read because no
* more data remains to be read
* @exception IOException if an I/O error occurs
*/
public char readChar()
throws IOException;
/**
* Read an int value.
*
* This method is the counterpart for the
* {@link java.io.DataOutput#writeInt} method.
*
* @return an int value
*
* @exception EOFException if the value could not be read because no
* more data remains to be read
* @exception IOException if an I/O error occurs
*/
public int readInt()
throws IOException;
/**
* Read a long value.
*
* This method is the counterpart for the
* {@link java.io.DataOutput#writeLong} method.
*
* @return a long value
*
* @exception EOFException if the value could not be read because no
* more data remains to be read
* @exception IOException if an I/O error occurs
*/
public long readLong()
throws IOException;
/**
* Read a float value.
*
* This method is the counterpart for the
* {@link java.io.DataOutput#writeFloat} method.
*
* @return a float value
*
* @exception EOFException if the value could not be read because no
* more data remains to be read
* @exception IOException if an I/O error occurs
*/
public float readFloat()
throws IOException;
/**
* Read a double value.
*
* This method is the counterpart for the
* {@link java.io.DataOutput#writeDouble} method.
*
* @return a double value
*
* @exception EOFException if the value could not be read because no
* more data remains to be read
* @exception IOException if an I/O error occurs
*/
public double readDouble()
throws IOException;
/**
* Reads the next "line" of text.
*
* This method does not have a counterpart in the
* {@link java.io.DataOutput} interface. Furthermore, this method is
* defined as operating on bytes and not on characters, and thus it
* should be selected for use only after careful consideration, as if
* it were deprecated (which it has been in java.io.DataInputStream).
*
* @return a line of text as a String
* @exception IOException if an I/O error occurs.
*/
public String readLine()
throws IOException;
/**
* Reads a String value.
*
* This method is the counterpart for the
* {@link java.io.DataOutput#writeUTF} method.
*
* @return a String value
*
* @exception java.io.UTFDataFormatException if the bytes that were
* read were not
* a valid UTF-8 encoded string
* @exception EOFException if the value could not be read because no
* more data remains to be read
* @exception IOException if an I/O error occurs
*/
public String readUTF()
throws IOException;
// ----- BufferInput methods ------------------------------------
/**
* Get the ReadBuffer object that this BufferInput is reading from.
*
* @return the underlying ReadBuffer object
*/
public ReadBuffer getBuffer();
/**
* Read a variable-length encoded UTF packed String. The major
* differences between this implementation and DataInput is that this
* supports null String values and is not limited to 64KB UTF-encoded
* values.
*
* @return a String value; may be null
*
* @exception IOException if an I/O error occurs
*/
public String readSafeUTF()
throws IOException;
/**
* Read an int value using a variable-length storage format as described
* by {@link WriteBuffer.BufferOutput#writePackedInt(int)}.
*
* @return an int value
*
* @exception IOException if an I/O error occurs
*/
public int readPackedInt()
throws IOException;
/**
* Read a long value using a variable-length storage format as described
* by {@link WriteBuffer.BufferOutput#writePackedLong(long)}.
*
* @return a long value
*
* @exception IOException if an I/O error occurs
*/
public long readPackedLong()
throws IOException;
/**
* Read cb bytes and return them as a ReadBuffer object.
*
* @param cb the number of bytes to read
*
* @return a ReadBuffer object composed of cb bytes read
* from the BufferInput
*
* @exception EOFException if the stream is exhausted before
* the number of bytes indicated could be read
* @exception IOException if an I/O error occurs
*/
public ReadBuffer readBuffer(int cb)
throws IOException;
/**
* Determine the current offset of this BufferInput within the
* underlying ReadBuffer.
*
* @return the offset of the next byte to read from the ReadBuffer
*/
public int getOffset();
/**
* Specify the offset of the next byte to read from the underlying
* ReadBuffer.
*
* @param of the offset of the next byte to read from the ReadBuffer
*
* @exception IndexOutOfBoundsException if of < 0 or
* of > getBuffer().length()
*/
public void setOffset(int of);
/**
* Returns an ObjectInputFilter (or null) that should be used by the caller
* to confirm / deny deserialization of a class encoded in this input stream.
*
* Note: the return type is agnostic of the ObjectInputFilter to support various JDK versions.
*
* @return null or an ObjectInputFilter that will permit (or not) the constructor
* of a class encoded in this stream.
*
* @see #setObjectInputFilter(Object)
*/
public default Object getObjectInputFilter()
{
return null;
}
/**
* Set the {@link #getObjectInputFilter() ObjectInputFilter} for this stream.
*
* The filter's checkInput method is expected to be called for each class
* and reference deserialized in the stream.
*
* @implSpec
* This method can set the ObjectInputFilter once.
*
* In Java version 17 and greater, the stream's ObjectInputFilter is set
* to the filter returned by invoking the
* {@link ExternalizableHelper#getConfigSerialFilterFactory() JVM-wide filter factory}
* with the {@link #getObjectInputFilter()} current filter} and the{@code filter} parameter.
*
*
* It is not permitted to replace a {@code non-null} filter with a
* {@code null} filter.
* If the {@linkplain #getObjectInputFilter() current filter} is {@code non-null},
* the value returned from the filter factory (or provided filter) must
* be {@code non-null}.
*
* @param oInputFilter an ObjectInputFilter instance as an Object to enable
* running with Java version 8 or higher, may be null
*
* @throws IllegalStateException if the filter factory returns {@code null}
* when the {@linkplain #getObjectInputFilter() current filter} is
* non-null, or if the filter has already been set.
*/
public default void setObjectInputFilter(Object oInputFilter)
{
// no-op
}
}
}