Fix #325

Author: cowtowncoder

release-notes/CREDITS

@@ -116,3 +116,5 @@ Alex Yursha (AlexYursha@github)
 Brad Hess (bdhess@github)
   * Contributed #323: Add `JsonParser.ALLOW_TRAILING_COMMA` to work for Arrays and Objects
    (2.9.0)
+  * Reported #325: `DataInput` backed parser should handle `EOFException` at end of doc
+   (2.9.0)

release-notes/VERSION

@@ -22,6 +22,8 @@ JSON library.
  (contributed by Alex Y)
 #323: Add `JsonParser.ALLOW_TRAILING_COMMA` to work for Arrays and Objects
  (contributed by Brad H)
+#325: `DataInput` backed parser should handle `EOFException` at end of doc
+ (reported by Brad H)
 
 2.8.4 (14-Oct-2016)
 

src/main/java/com/fasterxml/jackson/core/json/UTF8DataInputJsonParser.java

@@ -569,7 +569,12 @@ public JsonToken nextToken() throws IOException
         if (_tokenIncomplete) {
             _skipString(); // only strings can be partial
         }
-        int i = _skipWS();
+        int i = _skipWSOrEnd();
+        if (i < 0) { // end-of-input
+            // Close/release things like input source, symbol table and recyclable buffers
+            close();
+            return (_currToken = null);
+        }
         // clear any data retained so far
         _binaryValue = null;
         _tokenInputRow = _currInputRow;
@@ -2197,6 +2202,45 @@ private final int _skipWS() throws IOException
         }
     }
 
+    /**
+     * Alternative to {@link #_skipWS} that handles possible {@link EOFException}
+     * caused by trying to read past the end of {@link InputData}.
+     *
+     * @since 2.9
+     */
+    private final int _skipWSOrEnd() throws IOException
+    {
+        int i = _nextByte;
+        if (i < 0) {
+            try {
+                i = _inputData.readUnsignedByte();
+            } catch (EOFException e) {
+                return -1;
+            }
+        } else {
+            _nextByte = -1;
+        }
+        while (true) {
+            if (i > INT_SPACE) {
+                if (i == INT_SLASH || i == INT_HASH) {
+                    return _skipWSComment(i);
+                }
+                return i;
+            } else {
+                // 06-May-2016, tatu: Could verify validity of WS, but for now why bother.
+                //   ... but line number is useful thingy
+                if (i == INT_CR || i == INT_LF) {
+                    ++_currInputRow;
+                }
+            }
+            try {
+                i = _inputData.readUnsignedByte();
+            } catch (EOFException e) {
+                return -1;
+            }
+        }
+    }
+    
     private final int _skipWSComment(int i) throws IOException
     {
         while (true) {

src/test/java/com/fasterxml/jackson/core/read/DataInputTest.java

@@ -0,0 +1,42 @@
+package com.fasterxml.jackson.core.read;
+
+import com.fasterxml.jackson.core.*;
+
+/* Additional testing for {@link java.io.DataInput} specific
+ * challenges for parsing.
+ */
+public class DataInputTest
+    extends com.fasterxml.jackson.core.BaseTest
+{
+    private final JsonFactory JSON_F = new JsonFactory();
+
+    public void testEOFAfterArray() throws Exception
+    {
+        JsonParser p = createParser(JSON_F, MODE_DATA_INPUT, "[ 1 ]  ");
+        assertToken(JsonToken.START_ARRAY, p.nextToken());
+        assertToken(JsonToken.VALUE_NUMBER_INT, p.nextToken());
+        assertToken(JsonToken.END_ARRAY, p.nextToken());
+        assertNull(p.nextToken());
+        p.close();
+    }
+
+    public void testEOFAfterObject() throws Exception
+    {
+        JsonParser p = createParser(JSON_F, MODE_DATA_INPUT, "{ \"value\" : true }");
+        assertToken(JsonToken.START_OBJECT, p.nextToken());
+        assertToken(JsonToken.FIELD_NAME, p.nextToken());
+        assertToken(JsonToken.VALUE_TRUE, p.nextToken());
+        assertToken(JsonToken.END_OBJECT, p.nextToken());
+        assertNull(p.nextToken());
+        p.close();
+    }
+
+    public void testEOFAfterScalar() throws Exception
+    {
+        JsonParser p = createParser(JSON_F, MODE_DATA_INPUT, "\"foobar\" ");
+        assertToken(JsonToken.VALUE_STRING, p.nextToken());
+        assertEquals("foobar", p.getText());
+        assertNull(p.nextToken());
+        p.close();
+    }
+}

src/test/java/com/fasterxml/jackson/core/testsupport/MockDataInput.java

@@ -42,7 +42,7 @@ public boolean readBoolean() throws IOException {
     public byte readByte() throws IOException {
         int ch = _input.read();
         if (ch < 0) {
-            throw new IOException("End-of-input for readByte()");
+            throw new EOFException("End-of-input for readByte()");
         }
         return (byte) ch;
     }