diff --git a/spring-core/src/main/java/org/springframework/core/io/buffer/DefaultDataBuffer.java b/spring-core/src/main/java/org/springframework/core/io/buffer/DefaultDataBuffer.java index 8d9fcda643..d463af842a 100644 --- a/spring-core/src/main/java/org/springframework/core/io/buffer/DefaultDataBuffer.java +++ b/spring-core/src/main/java/org/springframework/core/io/buffer/DefaultDataBuffer.java @@ -80,14 +80,16 @@ public class DefaultDataBuffer implements DataBuffer { /** * Directly exposes the native {@code ByteBuffer} that this buffer is based - * on also updating the {@code ByteBuffer's} position and limit to match - * the current {@link #readPosition()} and {@link #readableByteCount()}. + * on. The {@linkplain ByteBuffer#position() position} of the returned + * {@code ByteBuffer} is set to the {@linkplain #readPosition() read + * position}, and the {@linkplain ByteBuffer#limit()} to the + * {@linkplain #writePosition() write position}. * @return the wrapped byte buffer */ public ByteBuffer getNativeBuffer() { - this.byteBuffer.position(this.readPosition); - this.byteBuffer.limit(readableByteCount()); - return this.byteBuffer; + return this.byteBuffer.duplicate() + .position(this.readPosition) + .limit(this.writePosition); } private void setNativeBuffer(ByteBuffer byteBuffer) { diff --git a/spring-core/src/test/java/org/springframework/core/io/buffer/DefaultDataBufferTests.java b/spring-core/src/test/java/org/springframework/core/io/buffer/DefaultDataBufferTests.java new file mode 100644 index 0000000000..c91772af79 --- /dev/null +++ b/spring-core/src/test/java/org/springframework/core/io/buffer/DefaultDataBufferTests.java @@ -0,0 +1,58 @@ +/* + * Copyright 2024-2024 the original author or authors. + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * https://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +package org.springframework.core.io.buffer; + +import java.nio.ByteBuffer; +import java.nio.charset.StandardCharsets; + +import org.junit.jupiter.api.Test; + +import static org.assertj.core.api.Assertions.assertThat; +import static org.springframework.core.io.buffer.DataBufferUtils.release; + +/** + * Tests for {@link DefaultDataBuffer}. + * + * @author Injae Kim + * @since 6.2 + */ +class DefaultDataBufferTests { + + private final DefaultDataBufferFactory bufferFactory = new DefaultDataBufferFactory(); + + @Test // gh-30967 + void getNativeBuffer() { + DefaultDataBuffer dataBuffer = this.bufferFactory.allocateBuffer(256); + dataBuffer.write("0123456789", StandardCharsets.UTF_8); + + byte[] result = new byte[7]; + dataBuffer.read(result); + assertThat(result).isEqualTo("0123456".getBytes(StandardCharsets.UTF_8)); + + ByteBuffer nativeBuffer = dataBuffer.getNativeBuffer(); + assertThat(nativeBuffer.position()).isEqualTo(7); + assertThat(dataBuffer.readPosition()).isEqualTo(7); + assertThat(nativeBuffer.limit()).isEqualTo(10); + assertThat(dataBuffer.writePosition()).isEqualTo(10); + assertThat(nativeBuffer.capacity()).isEqualTo(256); + assertThat(dataBuffer.capacity()).isEqualTo(256); + + + release(dataBuffer); + } + +}