feat!: support read-only ID services

saalfeldlab · Aug 9, 2024 · 849e004 · 849e004
1 parent a5d1051
commit 849e004
Show file tree

Hide file tree

Showing 4 changed files with 13 additions and 18 deletions.
diff --git a/src/main/java/org/janelia/saalfeldlab/paintera/id/N5IdService.java b/src/main/java/org/janelia/saalfeldlab/paintera/id/N5IdService.java
@@ -1,32 +1,28 @@
 package org.janelia.saalfeldlab.paintera.id;
 
+import org.janelia.saalfeldlab.n5.N5Reader;
 import org.janelia.saalfeldlab.n5.N5Writer;
 
 
 import java.util.stream.LongStream;
 
 public class N5IdService implements IdService {
 
-	private final N5Writer n5;
+	private final N5Reader n5;
 
 	private final String dataset;
 
 	private long next;
 	private long nextTemp = IdService.FIRST_TEMPORARY_ID;
 
-	public N5IdService(final N5Writer n5, final String dataset, final long next) {
+	public N5IdService(final N5Reader n5, final String dataset, final long next) {
 
 		super();
 		this.n5 = n5;
 		this.dataset = dataset;
 		this.next = next;
 	}
 
-	public N5Writer getWriter() {
-
-		return n5;
-	}
-
 	public String getDataset() {
 
 		return dataset;
@@ -74,8 +70,9 @@ public synchronized long[] next(final int n) {
 	}
 
 	private void serializeMaxId() {
-
-		n5.setAttribute(dataset, "maxId", next);
+		if (n5 instanceof N5Writer) {
+			((N5Writer)n5).setAttribute(dataset, "maxId", next);
+		}
 	}
 
 	@Override

diff --git a/src/main/java/org/janelia/saalfeldlab/util/n5/N5FragmentSegmentAssignmentPersister.java b/src/main/java/org/janelia/saalfeldlab/util/n5/N5FragmentSegmentAssignmentPersister.java
@@ -28,11 +28,6 @@ public N5FragmentSegmentAssignmentPersister(N5Writer writer, String dataset) {
 		LOG.debug("Creating {} with writer {} and dataset {}", getClass().getName(), this.writer, this.dataset);
 	}
 
-	public N5Writer getWriter() {
-
-		return this.writer;
-	}
-
 	public String getDataset() {
 
 		return this.dataset;

diff --git a/src/main/kotlin/org/janelia/saalfeldlab/paintera/state/label/n5/N5BackendPainteraDataset.kt b/src/main/kotlin/org/janelia/saalfeldlab/paintera/state/label/n5/N5BackendPainteraDataset.kt
@@ -81,7 +81,7 @@ class N5BackendPainteraDataset<D, T>(
 
 	//FIXME Caleb: same as above with idService
 	override fun createIdService(source: DataSource<D, T>): IdService {
-		return metadataState.writer?.let {
+		return (metadataState.writer ?: metadataState.reader)?.let {
 			N5Helpers.idService(it, dataset)
 		} ?: IdService.IdServiceNotProvided()
 	}

diff --git a/src/main/kotlin/org/janelia/saalfeldlab/util/n5/N5Helpers.kt b/src/main/kotlin/org/janelia/saalfeldlab/util/n5/N5Helpers.kt
@@ -413,12 +413,15 @@ object N5Helpers {
 	 */
 	@JvmStatic
 	@Throws(MaxIDNotSpecified::class, IOException::class)
-	fun idService(n5: N5Writer, dataset: String?): IdService {
+	fun idService(n5: N5Reader, dataset: String?): IdService {
 		LOG.debug { "Requesting id service for $n5:$dataset" }
 		val maxId = n5.getAttribute(dataset, "maxId", Long::class.java)
 		LOG.debug { "Found maxId=$maxId" }
-		if (maxId == null) throw MaxIDNotSpecified("Required attribute `maxId' not specified for dataset `$dataset' in container `$n5'.")
-		return N5IdService(n5, dataset, maxId)
+		return when {
+			maxId == null && n5 is N5Writer -> throw MaxIDNotSpecified("Required attribute `maxId' not specified for dataset `$dataset' in container `$n5'.")
+			maxId == null -> N5IdService(n5, dataset, 1)
+			else -> N5IdService(n5, dataset, maxId)
+		}
 	}
 
 	/**