diff --git a/spring-core/src/main/java/org/springframework/core/io/buffer/DataBufferInputStream.java b/spring-core/src/main/java/org/springframework/core/io/buffer/DataBufferInputStream.java index 33135285ae95..669394369c25 100644 --- a/spring-core/src/main/java/org/springframework/core/io/buffer/DataBufferInputStream.java +++ b/spring-core/src/main/java/org/springframework/core/io/buffer/DataBufferInputStream.java @@ -18,6 +18,8 @@ import java.io.IOException; import java.io.InputStream; +import java.io.OutputStream; +import java.util.Objects; import org.springframework.util.Assert; @@ -103,10 +105,44 @@ public void close() { this.closed = true; } + @Override + public byte[] readNBytes(int len) throws IOException { + if (len < 0) { + throw new IllegalArgumentException("len < 0"); + } + checkClosed(); + int size = Math.min(available(), len); + byte[] out = new byte[size]; + this.dataBuffer.read(out); + return out; + } + + @Override + public long skip(long n) throws IOException { + checkClosed(); + if (n <= 0) { + return 0L; + } + int skipped = Math.min(available(), n > Integer.MAX_VALUE ? Integer.MAX_VALUE : (int) n); + this.dataBuffer.readPosition(Math.min(this.end, this.dataBuffer.readPosition() + skipped)); + return skipped; + } + + @Override + public long transferTo(OutputStream out) throws IOException { + Objects.requireNonNull(out, "out"); + checkClosed(); + if (available() == 0) { + return 0L; + } + byte[] buf = readAllBytes(); + out.write(buf); + return buf.length; + } + private void checkClosed() throws IOException { if (this.closed) { throw new IOException("DataBufferInputStream is closed"); } } - } diff --git a/spring-core/src/test/java/org/springframework/core/io/buffer/DataBufferTests.java b/spring-core/src/test/java/org/springframework/core/io/buffer/DataBufferTests.java index a91aab01d37e..d20bcf64df6a 100644 --- a/spring-core/src/test/java/org/springframework/core/io/buffer/DataBufferTests.java +++ b/spring-core/src/test/java/org/springframework/core/io/buffer/DataBufferTests.java @@ -16,6 +16,7 @@ package org.springframework.core.io.buffer; +import java.io.ByteArrayOutputStream; import java.io.InputStream; import java.io.OutputStream; import java.nio.ByteBuffer; @@ -341,6 +342,48 @@ void inputStream(DataBufferFactory bufferFactory) throws Exception { assertThat(len).isEqualTo(3); assertThat(bytes).containsExactly('c', 'd', 'e'); + buffer.readPosition(0); + inputStream = buffer.asInputStream(); + assertThat(inputStream.readAllBytes()).asString().isEqualTo("abcde"); + assertThat(inputStream.available()).isEqualTo(0); + assertThat(inputStream.readAllBytes()).isEmpty(); + + buffer.readPosition(0); + inputStream = buffer.asInputStream(); + inputStream.mark(5); + assertThat(inputStream.readNBytes(0)).isEmpty(); + assertThat(inputStream.readNBytes(1000)).asString().isEqualTo("abcde"); + inputStream.reset(); + assertThat(inputStream.readNBytes(3)).asString().isEqualTo("abc"); + assertThat(inputStream.readNBytes(2)).asString().isEqualTo("de"); + assertThat(inputStream.readNBytes(10)).isEmpty(); + + buffer.readPosition(0); + inputStream = buffer.asInputStream(); + inputStream.mark(5); + assertThat(inputStream.skip(1)).isEqualTo(1); + assertThat(inputStream.readAllBytes()).asString().isEqualTo("bcde"); + assertThat(inputStream.skip(10)).isEqualTo(0); + assertThat(inputStream.available()).isEqualTo(0); + inputStream.reset(); + assertThat(inputStream.skip(100)).isEqualTo(5); + assertThat(inputStream.available()).isEqualTo(0); + + buffer.readPosition(0); + inputStream = buffer.asInputStream(); + inputStream.mark(5); + ByteArrayOutputStream out = new ByteArrayOutputStream(); + assertThat(inputStream.transferTo(out)).isEqualTo(5); + assertThat(out.toByteArray()).asString().isEqualTo("abcde"); + assertThat(inputStream.available()).isEqualTo(0); + out.reset(); + inputStream.reset(); + assertThat(inputStream.read()).isEqualTo('a'); + assertThat(inputStream.transferTo(out)).isEqualTo(4); + assertThat(out.toByteArray()).asString().isEqualTo("bcde"); + assertThat(inputStream.available()).isEqualTo(0); + assertThat(inputStream.transferTo(OutputStream.nullOutputStream())).isEqualTo(0); + release(buffer); }