[sis] 02/02: More robust parsing of `GDAL_NODATA` tag (may be an empty string).

[desruisseaux]

This is an automated email from the ASF dual-hosted git repository.

desruisseaux pushed a commit to branch geoapi-4.0
in repository https://gitbox.apache.org/repos/asf/sis.git

commit 5740d3f65709a135cf863aeca9e954dca478db40
Author: Martin Desruisseaux <martin.desruisse...@geomatys.com>
AuthorDate: Sat Oct 30 22:08:32 2021 +0200

    More robust parsing of `GDAL_NODATA` tag (may be an empty string).
---
 .../java/org/apache/sis/storage/geotiff/Type.java  | 26 +++++++++++++---------
 1 file changed, 15 insertions(+), 11 deletions(-)

diff --git 
a/storage/sis-geotiff/src/main/java/org/apache/sis/storage/geotiff/Type.java 
b/storage/sis-geotiff/src/main/java/org/apache/sis/storage/geotiff/Type.java
index c7ccbb7..893b0e5 100644
--- a/storage/sis-geotiff/src/main/java/org/apache/sis/storage/geotiff/Type.java
+++ b/storage/sis-geotiff/src/main/java/org/apache/sis/storage/geotiff/Type.java
@@ -369,23 +369,27 @@ enum Type {
             return ArraysExt.resize(lines, count);
         }
 
-        private String readString(final ChannelDataInput input, final long 
count) throws IOException {
+        /** Returns the singleton string, or {@code null} if none. */
+        private String readString(final ChannelDataInput input, final long 
count, final boolean mandatory) throws IOException {
             final String[] lines = readString(input, count, 
StandardCharsets.US_ASCII);
-            final String value = lines[0];
-            for (int i=1; i<lines.length; i++) {
-                if (!value.equals(lines[i])) {
-                    throw new 
IllegalArgumentException(Errors.format(Errors.Keys.UnexpectedArrayLength_2, 1, 
count));
-                }
+            if (lines.length != 0) {
+                final String value = lines[0];
+                int i = 1;
+                do if (i >= lines.length) return value;
+                while (value.equals(lines[i++]));
+            } else if (!mandatory) {
+                return null;
             }
-            return value;
+            throw new 
IllegalArgumentException(Errors.format(Errors.Keys.UnexpectedArrayLength_2, 1, 
lines.length));
         }
 
         @Override public long readLong(final ChannelDataInput input, final 
long count) throws IOException {
-            return Long.parseLong(readString(input, count));
+            return Long.parseLong(readString(input, count, true));
         }
 
         @Override public double readDouble(final ChannelDataInput input, final 
long count) throws IOException {
-            return Double.parseDouble(readString(input, count));
+            final String text = readString(input, count, false);
+            return (text != null) ? Double.parseDouble(text) : Double.NaN;
         }
 
         @Override public Object readArray(final ChannelDataInput input, final 
int count) throws IOException {
@@ -393,7 +397,7 @@ enum Type {
         }
 
         @Override public Object readObject(final ChannelDataInput input, final 
long count) throws IOException {
-            return readString(input, count);
+            return readString(input, count, false);
         }
     };
 
@@ -634,7 +638,7 @@ enum Type {
      *
      * @param  input  the input from where to read the values.
      * @param  count  the amount of values.
-     * @return the value as a Java array.
+     * @return the value as a Java array. May be an empty array.
      * @throws IOException if an error occurred while reading the stream.
      * @throws UnsupportedOperationException if this type is {@link 
#UNDEFINED}.
      */