Use String for JSON directly (does not pass ValueBinderTest)

@@ -379,7 +379,7 @@ private Object writeReplace() {
 builder.set(fieldName).to((String) value);
 break;
 case JSON:
-builder.set(fieldName).to((Json) value);
+builder.set(fieldName).to((String) value);
 break;
 case BYTES:
 builder.set(fieldName).to((ByteArray) value);
@@ -408,7 +408,7 @@ private Object writeReplace() {
 builder.set(fieldName).toStringArray((Iterable<String>) value);
 break;
 case JSON:
-builder.set(fieldName).toJsonArray((Iterable<Json>) value);
+builder.set(fieldName).toJsonArray((Iterable<String>) value);
 break;
 case BYTES:
 builder.set(fieldName).toBytesArray((Iterable<ByteArray>) value);
@@ -486,11 +486,9 @@ private static Object decodeValue(Type fieldType, com.google.protobuf.Value prot
 case NUMERIC:
 return new BigDecimal(proto.getStringValue());
 case STRING:
-checkType(fieldType, proto, KindCase.STRING_VALUE);
-return proto.getStringValue();
 case JSON:
 checkType(fieldType, proto, KindCase.STRING_VALUE);
-return new Json(proto.getStringValue());
+return proto.getStringValue();
 case BYTES:
 checkType(fieldType, proto, KindCase.STRING_VALUE);
 return ByteArray.fromBase64(proto.getStringValue());
@@ -572,7 +570,7 @@ public String apply(com.google.protobuf.Value input) {
 list.add(
 value.getKindCase() == KindCase.NULL_VALUE
 ? null
-: new Json(value.getStringValue()));
+: value.getStringValue());
 }
 return list;
 }
@@ -685,8 +683,8 @@ protected String getStringInternal(int columnIndex) {
 }
 
 @Override
-protected Json getJsonInternal(int columnIndex) {
-return (Json) rowData.get(columnIndex);
+protected String getJsonInternal(int columnIndex) {
+return (String) rowData.get(columnIndex);
 }
 
 @Override
@@ -763,8 +761,8 @@ protected List<String> getStringListInternal(int columnIndex) {
 
 @Override
 @SuppressWarnings("unchecked") // We know ARRAY<JSON> produces a List<JSON>.
-protected List<Json> getJsonListInternal(int columnIndex) {
-return Collections.unmodifiableList((List<Json>) rowData.get(columnIndex));
+protected List<String> getJsonListInternal(int columnIndex) {
+return Collections.unmodifiableList((List<String>) rowData.get(columnIndex));
 }
 
 @Override
@@ -1142,8 +1140,8 @@ static double valueProtoToFloat64(com.google.protobuf.Value proto) {
 + " \"Infinity\", \"-Infinity\", or \"NaN\" but was "
 + proto.getKindCase()
 + (proto.getKindCase() == KindCase.STRING_VALUE
-? " with value \"" + proto.getStringValue() + "\""
-: ""));
+? " with value \"" + proto.getStringValue() + "\""
+: ""));
 }
 return proto.getNumberValue();
 }
@@ -1297,7 +1295,7 @@ protected String getStringInternal(int columnIndex) {
 }
 
 @Override
-protected Json getJsonInternal(int columnIndex) {
+protected String getJsonInternal(int columnIndex) {
 return currRow().getJsonInternal(columnIndex);
 }
 
@@ -1357,7 +1355,7 @@ protected List<String> getStringListInternal(int columnIndex) {
 }
 
 @Override
-protected List<Json> getJsonListInternal(int columnIndex) {
+protected List<String> getJsonListInternal(int columnIndex) {
 return currRow().getJsonListInternal(columnIndex);
 }
 

@@ -43,7 +43,7 @@ public abstract class AbstractStructReader implements StructReader {
 
 protected abstract String getStringInternal(int columnIndex);
 
-protected abstract Json getJsonInternal(int columnIndex);
+protected abstract String getJsonInternal(int columnIndex);
 
 protected abstract ByteArray getBytesInternal(int columnIndex);
 
@@ -67,7 +67,7 @@ public abstract class AbstractStructReader implements StructReader {
 
 protected abstract List<String> getStringListInternal(int columnIndex);
 
-protected abstract List<Json> getJsonListInternal(int columnIndex);
+protected abstract List<String> getJsonListInternal(int columnIndex);
 
 protected abstract List<ByteArray> getBytesListInternal(int columnIndex);
 
@@ -163,13 +163,13 @@ public String getString(String columnName) {
 }
 
 @Override
-public Json getJson(int columnIndex) {
+public String getJson(int columnIndex) {
 checkNonNullOfType(columnIndex, Type.json(), columnIndex);
 return getJsonInternal(columnIndex);
 }
 
 @Override
-public Json getJson(String columnName) {
+public String getJson(String columnName) {
 int columnIndex = getColumnIndex(columnName);
 checkNonNullOfType(columnIndex, Type.json(), columnName);
 return getJsonInternal(columnIndex);
@@ -319,13 +319,13 @@ public List<String> getStringList(String columnName) {
 }
 
 @Override
-public List<Json> getJsonList(int columnIndex) {
+public List<String> getJsonList(int columnIndex) {
 checkNonNullOfType(columnIndex, Type.array(Type.json()), columnIndex);
 return getJsonListInternal(columnIndex);
 }
 
 @Override
-public List<Json> getJsonList(String columnName) {
+public List<String> getJsonList(String columnName) {
 int columnIndex = getColumnIndex(columnName);
 checkNonNullOfType(columnIndex, Type.array(Type.json()), columnName);
 return getJsonListInternal(columnIndex);

@@ -157,13 +157,13 @@ public String getString(String columnName) {
 }
 
 @Override
-public Json getJson(int columnIndex) {
+public String getJson(int columnIndex) {
 checkValidState();
 return delegate.get().getJson(columnIndex);
 }
 
 @Override
-public Json getJson(String columnName) {
+public String getJson(String columnName) {
 checkValidState();
 return delegate.get().getJson(columnName);
 }
@@ -299,13 +299,13 @@ public List<String> getStringList(String columnName) {
 }
 
 @Override
-public List<Json> getJsonList(int columnIndex) {
+public List<String> getJsonList(int columnIndex) {
 checkValidState();
 return delegate.get().getJsonList(columnIndex);
 }
 
 @Override
-public List<Json> getJsonList(String columnName) {
+public List<String> getJsonList(String columnName) {
 checkValidState();
 return delegate.get().getJsonList(columnName);
 }

@@ -193,7 +193,7 @@ protected String getStringInternal(int columnIndex) {
 }
 
 @Override
-protected Json getJsonInternal(int columnIndex) {
+protected String getJsonInternal(int columnIndex) {
 return values.get(columnIndex).getJson();
 }
 
@@ -258,7 +258,7 @@ protected List<String> getStringListInternal(int columnIndex) {
 }
 
 @Override
-protected List<Json> getJsonListInternal(int columnIndex) {
+protected List<String> getJsonListInternal(int columnIndex) {
 return values.get(columnIndex).getJsonArray();
 }
 

@@ -114,11 +114,11 @@ public interface StructReader {
 /** Returns the value of a non-{@code NULL} column with type {@link Type#string()}. */
 String getString(String columnName);
 
-/** Returns the value of a non-{@code NULL} column with type {@link Type#json()}. */
-Json getJson(int columnIndex);
+/** Returns the value of a non-{@code NULL} column with type {@link Type#string()}. */
+String getJson(int columnIndex);
 
-/** Returns the value of a non-{@code NULL} column with type {@link Type#json()}. */
-Json getJson(String columnName);
+/** Returns the value of a non-{@code NULL} column with type {@link Type#string()}. */
+String getJson(String columnName);
 
 /** Returns the value of a non-{@code NULL} column with type {@link Type#bytes()}. */
 ByteArray getBytes(int columnIndex);
@@ -224,11 +224,11 @@ public interface StructReader {
 /** Returns the value of a non-{@code NULL} column with type {@code Type.array(Type.string())}. */
 List<String> getStringList(String columnName);
 
-/** Returns the value of a non-{@code NULL} column with type {@code Type.array(Type.json())}. */
-List<Json> getJsonList(int columnIndex);
+/** Returns the value of a non-{@code NULL} column with type {@code Type.array(Type.string())}. */
+List<String> getJsonList(int columnIndex);
 
-/** Returns the value of a non-{@code NULL} column with type {@code Type.array(Type.json())}. */
-List<Json> getJsonList(String columnName);
+/** Returns the value of a non-{@code NULL} column with type {@code Type.array(Type.string())}. */
+List<String> getJsonList(String columnName);
 
 /** Returns the value of a non-{@code NULL} column with type {@code Type.array(Type.bytes())}. */
 List<ByteArray> getBytesList(int columnIndex);