minor improvements

src/main/java/org/takes/rq/ChunkedInputStream.java

@@ -42,6 +42,70 @@
  */
 final class ChunkedInputStream extends InputStream {
 
+    /**
+     * Empty value for checking the result.
+     */
+    private static final int EMPTY_VALUE = -1;
+
+    /**
+     * Default radix value.
+     */
+    private static final int DEFAULT_RADIX = 16;
+
+    /**
+     * Double slash value.
+     */
+    private static final int DOUBLE_SLASH = '\\';
+
+    /**
+     * Quoted string value.
+     */
+    private static final int QUOTED_STRING = '\"';
+
+    /**
+     * Next line value.
+     */
+    private static final int NEXT_LINE = '\n';
+
+    /**
+     * R value.
+     */
+    private static final int R_VALUE = '\r';
+
+    /**
+     * Semicolon value.
+     */
+    private static final int SEMICOLON = ';';
+
+    /**
+     * Exception for bad state.
+     */
+    private static final String BAD_STATE = "Bad state";
+
+    /**
+     * Exception for bad chunk.
+     */
+    private static final String BAD_CHUNK_SIZE = "Bad chunk size: %s";
+
+    /**
+     * Exception for chunk stream end.
+     */
+    private static final String END_OF_STREAM = "chunked stream ended unexpectedly";
+
+    /**
+     * Exception for crlf expectation state.
+     */
+    private static final String CRLF_EXPECTED = "CRLF expected at end of chunk: ";
+
+    /**
+     * Exception for protocol violation.
+     */
+    private static final String BAD_PROTOCOL = String.format(
+        "%s%s",
+        "Protocol violation: Unexpected",
+        " single newline character in chunk size"
+    );
+
     /**
      * The inputstream that we're wrapping.
      */
@@ -85,7 +149,7 @@ public int read() throws IOException {
         }
         final int result;
         if (this.eof) {
-            result = -1;
+            result = ChunkedInputStream.EMPTY_VALUE;
         } else {
             ++this.pos;
             result = this.origin.read();
@@ -101,7 +165,7 @@ public int read(final byte[] buf, final int off, final int len)
         }
         final int result;
         if (this.eof) {
-            result = -1;
+            result = ChunkedInputStream.EMPTY_VALUE;
         } else {
             final int shift = Math.min(len, this.size - this.pos);
             final int count = this.origin.read(buf, off, shift);
@@ -137,7 +201,7 @@ private void readCrlf() throws IOException {
             throw new IOException(
                 String.format(
                     "%s %d%s%d",
-                    "CRLF expected at end of chunk: ",
+                    ChunkedInputStream.CRLF_EXPECTED,
                     crsymbol,
                     "/",
                     lfsymbol
@@ -174,7 +238,7 @@ private static int chunkSize(final InputStream stream)
         throws IOException {
         final ByteArrayOutputStream baos = ChunkedInputStream.sizeLine(stream);
         final String data = baos.toString(Charset.defaultCharset().name());
-        final int separator = data.indexOf(';');
+        final int separator = data.indexOf(ChunkedInputStream.SEMICOLON);
         final Text number = new Trimmed(
             new Unchecked<>(
                 new Ternary<>(
@@ -186,44 +250,20 @@ private static int chunkSize(final InputStream stream)
         );
         try {
             return Integer.parseInt(
-                new UncheckedText(
-                    number
-                ).asString(),
-                16
+                new UncheckedText(number).asString(),
+                ChunkedInputStream.DEFAULT_RADIX
             );
         } catch (final NumberFormatException ex) {
             throw new IOException(
                 String.format(
-                    "Bad chunk size: %s",
+                    ChunkedInputStream.BAD_CHUNK_SIZE,
                     baos.toString(Charset.defaultCharset().name())
                 ),
                 ex
             );
         }
     }
 
-    /**
-     * Possible states of FSM that used to find chunk size.
-     */
-    private enum State {
-        /**
-         * Normal.
-         */
-        NORMAL,
-        /**
-         * If \r was scanned.
-         */
-        R,
-        /**
-         * Inside quoted string.
-         */
-        QUOTED_STRING,
-        /**
-         * End.
-         */
-        END;
-    }
-
     /**
      * Extract line with chunk size from stream.
      * @param stream Input stream.
@@ -251,32 +291,26 @@ private static ByteArrayOutputStream sizeLine(final InputStream stream)
     private static State next(final InputStream stream, final State state,
         final ByteArrayOutputStream line) throws IOException {
         final int next = stream.read();
-        if (next == -1) {
-            throw new IOException("chunked stream ended unexpectedly");
+        if (next == ChunkedInputStream.EMPTY_VALUE) {
+            throw new IOException(ChunkedInputStream.END_OF_STREAM);
         }
         final State result;
         switch (state) {
             case NORMAL:
                 result = nextNormal(state, line, next);
                 break;
             case R:
-                if (next == '\n') {
+                if (next == ChunkedInputStream.NEXT_LINE) {
                     result = State.END;
                 } else {
-                    throw new IOException(
-                        String.format(
-                            "%s%s",
-                            "Protocol violation: Unexpected",
-                            " single newline character in chunk size"
-                        )
-                    );
+                    throw new IOException(ChunkedInputStream.BAD_PROTOCOL);
                 }
                 break;
             case QUOTED_STRING:
                 result = nextQuoted(stream, state, line, next);
                 break;
             default:
-                throw new IllegalStateException("Bad state");
+                throw new IllegalStateException(ChunkedInputStream.BAD_STATE);
         }
         return result;
     }
@@ -292,10 +326,10 @@ private static State nextNormal(final State state,
         final ByteArrayOutputStream line, final int next) {
         final State result;
         switch (next) {
-            case '\r':
+            case ChunkedInputStream.R_VALUE:
                 result = State.R;
                 break;
-            case '\"':
+            case ChunkedInputStream.QUOTED_STRING:
                 result = State.QUOTED_STRING;
                 break;
             default:
@@ -321,11 +355,11 @@ private static State nextQuoted(final InputStream stream, final State state,
         throws IOException {
         final State result;
         switch (next) {
-            case '\\':
+            case ChunkedInputStream.DOUBLE_SLASH:
                 result = state;
                 line.write(stream.read());
                 break;
-            case '\"':
+            case ChunkedInputStream.QUOTED_STRING:
                 result = State.NORMAL;
                 break;
             default:
@@ -335,4 +369,26 @@ private static State nextQuoted(final InputStream stream, final State state,
         }
         return result;
     }
+
+    /**
+     * Possible states of FSM that used to find chunk size.
+     */
+    private enum State {
+        /**
+         * Normal.
+         */
+        NORMAL,
+        /**
+         * If \r was scanned.
+         */
+        R,
+        /**
+         * Inside quoted string.
+         */
+        QUOTED_STRING,
+        /**
+         * End.
+         */
+        END;
+    }
 }