Create StoredDouble

1 files changed, 46 insertions, 0 deletions

diff --git a/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/task/util/file/StoredDouble.java b/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/task/util/file/StoredDouble.java
new file mode 100644
index 00000000000..3249dab1ca8
--- /dev/null
+++ b/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/task/util/file/StoredDouble.java
@@ -0,0 +1,46 @@
+// Copyright Yahoo. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.hosted.node.admin.task.util.file;
+
+import com.yahoo.vespa.hosted.node.admin.component.TaskContext;
+
+import java.nio.file.Path;
+import java.time.Instant;
+import java.util.Optional;
+import java.util.OptionalDouble;
+import java.util.function.Supplier;
+import java.util.logging.Logger;
+
+/**
+ * Class wrapping a float stored on disk
+ *
+ * @author freva
+ */
+public class StoredDouble implements Supplier<OptionalDouble> {
+
+    private static final Logger logger = Logger.getLogger(StoredDouble.class.getName());
+
+    private final UnixPath path;
+
+    public StoredDouble(Path path) {
+        this.path = new UnixPath(path);
+    }
+
+    @Override
+    public OptionalDouble get() {
+        return path.readUtf8FileIfExists().stream().mapToDouble(Double::parseDouble).findAny();
+    }
+
+    public void write(TaskContext taskContext, double value) {
+        path.writeUtf8File(Double.toString(value));
+        taskContext.log(logger, "Stored new double in %s: %f", path, value);
+    }
+
+    public void clear() {
+        path.deleteIfExists();
+    }
+
+    public Optional<Instant> getLastModifiedTime() {
+        return path.getAttributesIfExists().map(FileAttributes::lastModifiedTime);
+    }
+
+}