add CharBufferJmh

hutool-core/src/main/java/org/dromara/hutool/core/io/NioUtil.java

@@ -41,6 +41,11 @@ import java.nio.charset.Charset;
  */
 public class NioUtil {
 
+	/**
+	 * 默认小缓存大小 1024
+	 */
+	public static final int DEFAULT_SMALL_BUFFER_SIZE = 2 << 9;
+
 	/**
 	 * 默认缓存大小 8192
 	 */

hutool-core/src/main/java/org/dromara/hutool/core/io/buffer/FastByteBuffer.java

@@ -41,7 +41,7 @@ public class FastByteBuffer extends FastBuffer {
 	 * 构造
 	 */
 	public FastByteBuffer() {
-		this(IoUtil.DEFAULT_BUFFER_SIZE);
+		this(IoUtil.DEFAULT_SMALL_BUFFER_SIZE);
 	}
 
 	/**

hutool-core/src/main/java/org/dromara/hutool/core/io/buffer/FastCharBuffer.java

@@ -21,7 +21,8 @@ import org.dromara.hutool.core.lang.Assert;
 
 /**
  * 代码移植自jetbrick<br>
- * 快速字符缓冲，将数据存放在缓冲集中，取代以往的单一数组
+ * 快速字符缓冲，将数据存放在缓冲集中，取代以往的单一数组<br>
+ * 注意：此缓存在大量重复append时，性能比{@link StringBuilder}要好，但是{@link #toArray()}性能很差
  *
  * @author jetbrick, looly
  */
@@ -40,7 +41,7 @@ public class FastCharBuffer extends FastBuffer implements CharSequence, Appendab
 	 * 构造
 	 */
 	public FastCharBuffer() {
-		this(IoUtil.DEFAULT_BUFFER_SIZE);
+		this(IoUtil.DEFAULT_SMALL_BUFFER_SIZE);
 	}
 
 	/**

hutool-core/src/test/java/org/dromara/hutool/core/io/buffer/BufferUtilTest.java

@@ -14,16 +14,15 @@
  * limitations under the License.
  */
 
-package org.dromara.hutool.core.io;
+package org.dromara.hutool.core.io.buffer;
 
-import java.nio.ByteBuffer;
-
-import org.dromara.hutool.core.io.buffer.BufferUtil;
 import org.dromara.hutool.core.text.StrUtil;
 import org.dromara.hutool.core.util.CharsetUtil;
 import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.Test;
 
+import java.nio.ByteBuffer;
+
 /**
  * BufferUtil单元测试
  *

hutool-core/src/test/java/org/dromara/hutool/core/io/buffer/CharBufferJmh.java

@@ -0,0 +1,40 @@
+package org.dromara.hutool.core.io.buffer;
+
+import org.openjdk.jmh.annotations.*;
+
+import java.util.concurrent.TimeUnit;
+
+@BenchmarkMode(Mode.AverageTime)//每次执行平均花费时间
+@Warmup(iterations = 1, time = 1, timeUnit = TimeUnit.SECONDS) //预热1次调用
+@Measurement(iterations = 5, time = 1, timeUnit = TimeUnit.SECONDS) // 执行5此，每次1秒
+@Threads(1) //单线程
+@Fork(1) //
+@OutputTimeUnit(TimeUnit.NANOSECONDS) // 单位：纳秒
+@State(Scope.Benchmark) // 共享域
+public class CharBufferJmh {
+
+	private final int appendCount = 10000;
+	private String str;
+
+	@Setup
+	public void setup() {
+		str = "abc123你好";
+	}
+
+	@SuppressWarnings("MismatchedQueryAndUpdateOfStringBuilder")
+	@Benchmark
+	public void stringBuilderJmh() {
+		final StringBuilder stringBuilder = new StringBuilder(1024);
+		for (int i = 0; i < appendCount; i++) {
+			stringBuilder.append(str);
+		}
+	}
+
+	@Benchmark
+	public void fastCharBufferJmh() {
+		final FastCharBuffer fastCharBuffer = new FastCharBuffer(1024);
+		for (int i = 0; i < appendCount; i++) {
+			fastCharBuffer.append(str);
+		}
+	}
+}