fix

gradle.properties

@@ -3,8 +3,8 @@ group=com.kamesuta.mc
 modid=signpic
 modname=SignPicture
 version_major=2
-version_minor=5
-version_micro=1
+version_minor=6
+version_micro=0.beta
 version_minecraft=1.7.10
 version_forge=10.13.4.1558-1.7.10
 version_minforge=10.13.4.1558

src/main/java/com/kamesuta/mc/signpic/entry/content/meta/ContentCache.java

@@ -14,6 +14,16 @@ public CacheData createBlank() {
 		};
 	}
 
+	public String getURL() {
+		return this.cacheio.get().url;
+	}
+
+	public ContentCache setURL(final String url) {
+		this.cacheio.get().url = url;
+		this.cacheio.save();
+		return this;
+	}
+
 	public String getMime() {
 		return this.cacheio.get().mime;
 	}
@@ -73,6 +83,10 @@ public static class CacheData implements IData {
 		 * format version
 		 */
 		public int format = FormatVersion;
+		/**
+		 * content End URL
+		 */
+		public String url;
 		/**
 		 * content MIME type
 		 */

src/main/java/com/kamesuta/mc/signpic/http/download/ContentDownload.java

@@ -67,7 +67,7 @@ public void communicate() {
 			final String endid = ContentLocation.hash(end);
 			this.content.meta.setCacheID(endid);
 			final ContentCache cachemeta = new ContentCache(ContentLocation.cachemetaLocation(endid));
-			cachemeta.setDirty(false);
+			cachemeta.setURL(end);
 
 			final File cachefile = ContentLocation.cacheLocation(endid);
 			if (cachemeta.isAvailable()&&!cachemeta.isDirty()&&cachefile.exists()) {
@@ -76,6 +76,8 @@ public void communicate() {
 				return;
 			}
 
+			cachemeta.setDirty(false);
+
 			final HttpEntity entity = response.getEntity();
 			cachemeta.setMime(ContentType.getOrDefault(entity).getMimeType());