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Java ByteBuffer vs Netty ByteBuf
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| import java.nio.ByteBuffer; | |
| public class ByteBufferTest { | |
| public static void main(String[] args) { | |
| //byteBuffer 할당 | |
| ByteBuffer byteBuffer = ByteBuffer.allocate(11); | |
| System.out.println("byteBuffer is direct buffer : " + byteBuffer.isDirect()); | |
| System.out.println("byteBuffer capacity is : " + byteBuffer.capacity()); | |
| System.out.println("byteBuffer initial value : " + byteBuffer); | |
| //값 할당 | |
| byte[] bytes = "Netty".getBytes(); | |
| for (byte b : bytes) { | |
| byteBuffer.put(b); | |
| System.out.println("#byteBuffer value : " + byteBuffer); | |
| } | |
| //java.nio.BufferUnderflowException | |
| //byteBuffer.get(); | |
| // position to zero | |
| byteBuffer.rewind(); | |
| System.out.println((char) byteBuffer.get()); | |
| System.out.println("after get, byteBuffer value 0 : " + byteBuffer); | |
| System.out.println((char) byteBuffer.get()); | |
| System.out.println("after get, byteBuffer value 1 : " + byteBuffer); | |
| // limit -> position & position -> 0 | |
| byteBuffer.flip(); | |
| System.out.println(byteBuffer); | |
| System.out.println((char) byteBuffer.get(1)); | |
| } | |
| } |
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| import io.netty.buffer.ByteBuf; | |
| import io.netty.buffer.ByteBufAllocator; | |
| import io.netty.buffer.Unpooled; | |
| import java.nio.ByteBuffer; | |
| import java.nio.charset.Charset; | |
| public class ByteBufTest { | |
| public static void main(String[] args) { | |
| // 4 types of buffers | |
| ByteBuf heapBufferInPool = ByteBufAllocator.DEFAULT.heapBuffer(11); | |
| ByteBuf directBufferInPool = ByteBufAllocator.DEFAULT.directBuffer(11); | |
| ByteBuf heapBufferNotInPool = Unpooled.buffer(11); | |
| ByteBuf directBufferNotInPool = Unpooled.directBuffer(11); | |
| // how to manipulate buffer | |
| ByteBuf byteBuf = ByteBufAllocator.DEFAULT.heapBuffer(11); | |
| System.out.println(byteBuf.capacity()); | |
| System.out.println(byteBuf.isDirect()); | |
| byteBuf.writeInt(65537); | |
| System.out.println("readable bytes : " + byteBuf.readableBytes()); | |
| System.out.println("writable bytes : " + byteBuf.writableBytes()); | |
| System.out.println("is readable : " + byteBuf.isReadable()); | |
| byteBuf.clear(); | |
| System.out.println("readable bytes : " + byteBuf.readableBytes()); | |
| System.out.println("writable bytes : " + byteBuf.writableBytes()); | |
| String sourceString = "hello netty"; | |
| byteBuf.writeBytes(sourceString.getBytes()); | |
| System.out.println("readable bytes : " + byteBuf.readableBytes()); | |
| System.out.println("writable bytes : " + byteBuf.writableBytes()); | |
| System.out.println(byteBuf.toString(Charset.defaultCharset())); | |
| //change capacity | |
| byteBuf.capacity(6); | |
| System.out.println(byteBuf.toString(Charset.defaultCharset())); | |
| byteBuf.capacity(13); | |
| System.out.println(byteBuf.toString(Charset.defaultCharset())); | |
| byteBuf.writeBytes("world".getBytes()); | |
| System.out.println(byteBuf.toString(Charset.defaultCharset())); | |
| //convert byteBuffer to byteBuf | |
| ByteBuffer byteBuffer = ByteBuffer.wrap("hi".getBytes()); | |
| ByteBuf buf = Unpooled.wrappedBuffer(byteBuffer); | |
| System.out.println(buf.toString(Charset.defaultCharset())); | |
| } | |
| } |
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