src/org/redkale/util/ByteBufferWriter.java

@@ -0,0 +1,100 @@
+/*
+ * To change this license header, choose License Headers in Project Properties.
+ * To change this template file, choose Tools | Templates
+ * and open the template in the editor.
+ */
+package org.redkale.util;
+
+import java.nio.ByteBuffer;
+import java.util.function.Supplier;
+
+/**
+ * 以ByteBuffer为数据载体的Writer
+ *
+ * <p>
+ * 详情见: https://redkale.org
+ *
+ * @author zhangjx
+ */
+public class ByteBufferWriter {
+
+    private final Supplier<ByteBuffer> supplier;
+
+    private ByteBuffer[] buffers;
+
+    protected ByteBufferWriter(Supplier<ByteBuffer> supplier) {
+        this.supplier = supplier;
+    }
+
+    public static ByteBufferWriter create(Supplier<ByteBuffer> supplier) {
+        return new ByteBufferWriter(supplier);
+    }
+
+    private ByteBuffer getLastBuffer(int size) {
+        if (this.buffers == null) {
+            ByteBuffer buf = supplier.get();
+            this.buffers = Utility.append(this.buffers, buf);
+            return buf;
+        } else if (this.buffers[this.buffers.length - 1].remaining() < size) {
+            ByteBuffer buf = supplier.get();
+            this.buffers = Utility.append(this.buffers, buf);
+            return buf;
+        }
+        return this.buffers[this.buffers.length - 1];
+    }
+
+    public ByteBuffer[] toBuffers() {
+        if (buffers == null) return new ByteBuffer[0];
+        for (ByteBuffer buf : this.buffers) {
+            if (buf.position() != 0) buf.flip();
+        }
+        return this.buffers;
+    }
+
+    public ByteBufferWriter put(byte b) {
+        getLastBuffer(1).put(b);
+        return this;
+    }
+
+    public ByteBufferWriter put(short value) {
+        getLastBuffer(2).putShort(value);
+        return this;
+    }
+
+    public ByteBufferWriter putInt(int value) {
+        getLastBuffer(4).putInt(value);
+        return this;
+    }
+
+    public ByteBufferWriter putFloat(float value) {
+        getLastBuffer(4).putFloat(value);
+        return this;
+    }
+
+    public ByteBufferWriter putLong(long value) {
+        getLastBuffer(8).putLong(value);
+        return this;
+    }
+
+    public ByteBufferWriter putDouble(double value) {
+        getLastBuffer(8).putDouble(value);
+        return this;
+    }
+
+    public ByteBufferWriter put(byte[] src) {
+        return put(src, 0, src.length);
+    }
+
+    public ByteBufferWriter put(byte[] src, int offset, int length) {
+        ByteBuffer buf = getLastBuffer(1);
+        int remain = buf.remaining();
+        if (remain >= length) {
+            buf.put(src, offset, length);
+        } else {
+            buf.put(src, offset, remain);
+            put(src, offset + remain, length - remain);
+        }
+        return this;
+    }
+
+}