fixed VPack parsing (issue #80)

Author: Mark

src/main/java/com/arangodb/velocypack/VPackBuilder.java

@@ -729,9 +729,9 @@ protected VPackBuilder close(final boolean sort)
 			// subvalue
 			// for the index table
 			offsetSize = 1;
-		} else if ((size - 1 - tos) + 2 * in.size() <= 0xffff) {
+		} else if ((size - tos) + 2 * in.size() <= 0xffff) {
 			offsetSize = 2;
-		} else if (((size - 1 - tos) / 2) + 4 * in.size() / 2 <= Integer.MAX_VALUE/* 0xffffffffu */) {
+		} else if (((size - tos) / 2) + 4 * in.size() / 2 <= Integer.MAX_VALUE/* 0xffffffffu */) {
 			offsetSize = 4;
 		} else {
 			offsetSize = 8;

src/test/java/com/arangodb/velocypack/VPackBuilderTest.java

@@ -25,7 +25,9 @@
 import static org.junit.Assert.assertThat;
 import static org.junit.Assert.fail;
 
+import java.io.UnsupportedEncodingException;
 import java.math.BigInteger;
+import java.nio.charset.Charset;
 import java.util.Date;
 
 import org.junit.Test;
@@ -914,7 +916,28 @@ public void addBitInteger() {
 	@Test
 	public void objectWithByteSize256() {
 		final StringBuilder aa = new StringBuilder();
-		final int stringLength = 231;
+		final int stringLength = 256 - 25;
+		for (int i = 0; i < stringLength; ++i) {
+			aa.append("a");
+		}
+		final String foo = "foo";
+		final String bar1 = "bar1";
+		final String bar2 = "bar2";
+		final VPackSlice vpack = new VPackBuilder().add(ValueType.OBJECT).add(foo, ValueType.OBJECT).add(bar2, "")
+				.add(bar1, aa.toString()).close().close().slice();
+
+		assertThat(vpack.isObject(), is(true));
+		assertThat(vpack.get(foo).isObject(), is(true));
+		assertThat(vpack.get(foo).get(bar1).isString(), is(true));
+		assertThat(vpack.get(foo).get(bar1).getLength(), is(stringLength));
+		assertThat(vpack.get(foo).get(bar2).isString(), is(true));
+		assertThat(vpack.get(foo).get(bar2).getLength(), is(0));
+	}
+
+	@Test
+	public void objectWithByteSizeOver65536() {
+		final StringBuilder aa = new StringBuilder();
+		final int stringLength = 65536 - 25 - 8;
 		for (int i = 0; i < stringLength; ++i) {
 			aa.append("a");
 		}