Files
flatbuffers-bigfoot/java/com/google/flatbuffers/ByteBufferReadWriteBuf.java
Paulo Pinheiro cd88e6b2aa [Java][FlexBuffers] Abstract buffer access from ByteBuffer (#5743)
To read and build flexbuffers on Java, one needs to wrap the data
using  ByteBuffer. But for the common case of having ByteBuffers
backed by arrays, accessing from a ByteBuffer might be inefficient.

So this change introduces two interfaces: ReadBuf and ReadWriteBuf.
It allows one to read and writes data directly on an array. It also allow
 other buffer implementations to be used with flexbuffers.

Another change is that FlexBuffersBuilder backed by array allows
the buffer to grow with the increase of the message size. Something
that could not be done with ByteBuffer.
2020-02-21 11:46:40 -08:00

166 lines
3.1 KiB
Java

package com.google.flatbuffers;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
public class ByteBufferReadWriteBuf implements ReadWriteBuf {
private final ByteBuffer buffer;
public ByteBufferReadWriteBuf(ByteBuffer bb) {
this.buffer = bb;
this.buffer.order(ByteOrder.LITTLE_ENDIAN);
}
@Override
public boolean getBoolean(int index) {
return get(index) != 0;
}
@Override
public byte get(int index) {
return buffer.get(index);
}
@Override
public short getShort(int index) {
return buffer.getShort(index);
}
@Override
public int getInt(int index) {
return buffer.getInt(index);
}
@Override
public long getLong(int index) {
return buffer.getLong(index);
}
@Override
public float getFloat(int index) {
return buffer.getFloat(index);
}
@Override
public double getDouble(int index) {
return buffer.getDouble(index);
}
@Override
public String getString(int start, int size) {
return Utf8Safe.decodeUtf8Buffer(buffer, start, size);
}
@Override
public byte[] data() {
return buffer.array();
}
@Override
public void putBoolean(boolean value) {
buffer.put(value ? (byte)1 : (byte)0);
}
@Override
public void put(byte[] value, int start, int length) {
buffer.put(value, start, length);
}
@Override
public void put(byte value) {
buffer.put(value);
}
@Override
public void putShort(short value) {
buffer.putShort(value);
}
@Override
public void putInt(int value) {
buffer.putInt(value);
}
@Override
public void putLong(long value) {
buffer.putLong(value);
}
@Override
public void putFloat(float value) {
buffer.putFloat(value);
}
@Override
public void putDouble(double value) {
buffer.putDouble(value);
}
@Override
public void setBoolean(int index, boolean value) {
set(index, value ? (byte)1 : (byte)0);
}
@Override
public void set(int index, byte value) {
requestCapacity(index + 1);
buffer.put(index, value);
}
@Override
public void set(int index, byte[] value, int start, int length) {
requestCapacity(index + (length - start));
int curPos = buffer.position();
buffer.position(index);
buffer.put(value, start, length);
buffer.position(curPos);
}
@Override
public void setShort(int index, short value) {
requestCapacity(index + 2);
buffer.putShort(index, value);
}
@Override
public void setInt(int index, int value) {
requestCapacity(index + 4);
buffer.putInt(index, value);
}
@Override
public void setLong(int index, long value) {
requestCapacity(index + 8);
buffer.putLong(index, value);
}
@Override
public void setFloat(int index, float value) {
requestCapacity(index + 4);
buffer.putFloat(index, value);
}
@Override
public void setDouble(int index, double value) {
requestCapacity(index + 8);
buffer.putDouble(index, value);
}
@Override
public int writePosition() {
return buffer.position();
}
@Override
public int limit() {
return buffer.limit();
}
@Override
public boolean requestCapacity(int capacity) {
return capacity <= buffer.limit();
}
}