refactor: Remove dead code in ByteBufferInputStream (#5742)

Reusing this code for the JS implementation of flight/barrage, and
noticed some dead/unused code.

Partial #188

IO/src/main/java/io/deephaven/io/streams/ByteBufferInputStream.java

@@ -10,37 +10,27 @@
 import java.nio.BufferUnderflowException;
 import java.nio.ByteBuffer;
 
-import io.deephaven.base.string.cache.CharSequenceAdapterBuilder;
-import io.deephaven.base.string.cache.StringCache;
 import org.jetbrains.annotations.NotNull;
 
 /**
  * This is an InputStream implementation which reads from a java.nio.ByteBuffer. If a read operation crosses the end of
  * the buffer, the BufferUnderflowException is converted to an EOFException.
- *
- * The stream contains no state other than that in in the buffer itself, so the buffer can be exchanged at will with the
+ * <p>
+ * The stream contains no state other than that in the buffer itself, so the buffer can be exchanged at will with the
  * setBuffer() method.
+ * <p>
+ * Endianness is determined by the provided buffer itself.
  */
 public class ByteBufferInputStream extends java.io.InputStream implements DataInput {
 
     /** the buffer from which we read */
     protected ByteBuffer buf;
 
-    private char[] utfChars;
-
-    /**
-     * The DataOutput interface always writes bytes in big-endian order, while ByteBuffer allows the order to be big- or
-     * little-endian. Set this flag true to assume that the buffer is bid-endian, or false to check the buffer's order
-     * at each write.
-     */
-    // protected static final boolean ASSUME_BIG_ENDIAN = true;
-
     /**
      * Construct a new stream which reads from a byte buffer/
      */
     public ByteBufferInputStream(ByteBuffer buf) {
         this.buf = buf;
-        this.utfChars = new char[0];
     }
 
     /**
@@ -64,7 +54,7 @@ public int read() throws IOException {
     }
 
     @Override
-    public int read(byte b[]) throws IOException {
+    public int read(byte[] b) throws IOException {
         int n = Math.min(buf.remaining(), b.length);
         if (n == 0 && b.length > 0) {
             return -1;
@@ -74,7 +64,7 @@ public int read(byte b[]) throws IOException {
     }
 
     @Override
-    public int read(byte b[], int off, int len) throws IOException {
+    public int read(byte[] b, int off, int len) throws IOException {
         int n = Math.min(buf.remaining(), len);
         if (n == 0 && len > 0) {
             return -1;
@@ -123,7 +113,7 @@ public boolean markSupported() {
     // -----------------------------------------------------------------------------------
 
     @Override
-    public void readFully(byte b[]) throws IOException {
+    public void readFully(byte[] b) throws IOException {
         try {
             buf.get(b, 0, b.length);
         } catch (BufferUnderflowException x) {
@@ -132,7 +122,7 @@ public void readFully(byte b[]) throws IOException {
     }
 
     @Override
-    public void readFully(byte b[], int off, int len) throws IOException {
+    public void readFully(byte[] b, int off, int len) throws IOException {
         try {
             buf.get(b, off, len);
         } catch (BufferUnderflowException x) {
@@ -307,6 +297,7 @@ public String readLine() throws IOException {
         return new String(chars);
     }
 
+    @NotNull
     @Override
     public String readUTF() throws IOException {
         int length = 0;
@@ -341,48 +332,4 @@ public String readUTF() throws IOException {
 
         return new String(chars, 0, length);
     }
-
-    public String readUTF(@NotNull final CharSequenceAdapterBuilder output,
-            @NotNull final StringCache<String> cache) throws IOException {
-        readUTF(output);
-        return cache.getCachedString(output);
-    }
-
-    public void readUTF(@NotNull final CharSequenceAdapterBuilder output) throws IOException {
-        int total = readUnsignedShort();
-
-        output.clear().reserveCapacity(total);
-
-        while (total > 0) {
-            final int b1 = buf.get();
-            if ((b1 & 0x80) == 0) {
-                output.append((char) (b1 & 0xff));
-                total--;
-            } else if ((b1 & 0xe0) == 0xc0) {
-                final int b2 = buf.get();
-                if ((b2 & 0xc0) != 0x80) {
-                    throw new UTFDataFormatException("malformed second byte " + b2);
-                }
-                output.append((char) (((b1 & 0x1F) << 6) | (b2 & 0x3F)));
-                total -= 2;
-            } else if ((b1 & 0xf0) == 0xe0) {
-                final int b2 = buf.get();
-                final int b3 = buf.get();
-                if ((b2 & 0xc0) != 0x80 || (b3 & 0xc0) != 0x80) {
-                    throw new UTFDataFormatException("malformed second byte " + b2 + " or third byte " + b3);
-                }
-                output.append((char) (((b1 & 0x0F) << 12) | ((b2 & 0x3F) << 6) | (b3 & 0x3F)));
-                total -= 3;
-            } else {
-                throw new UTFDataFormatException("malformed first byte " + b1);
-            }
-        }
-    }
-
-    public void read(ByteBuffer dest, int length) {
-        final int sourceLimit = buf.limit();
-        buf.limit(buf.position() + length); // Constrain buf.remaining() to length
-        dest.put(buf);
-        buf.limit(sourceLimit);
-    }
 }