1 files changed, 46 insertions, 0 deletions
diff --git a/container-core/src/main/java/com/yahoo/container/logging/FormatUtil.java b/container-core/src/main/java/com/yahoo/container/logging/FormatUtil.java
new file mode 100644
index 00000000000..ee780ad2a83
--- /dev/null
+++ b/container-core/src/main/java/com/yahoo/container/logging/FormatUtil.java
@@ -0,0 +1,46 @@
+// Copyright Verizon Media. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.container.logging;
+
+import com.fasterxml.jackson.core.JsonGenerator;
+
+import java.io.IOException;
+import java.time.Duration;
+import java.time.Instant;
+
+/**
+ * @author bjorncs
+ */
+class FormatUtil {
+
+    private FormatUtil() {}
+
+    static void writeSecondsField(JsonGenerator generator, String fieldName, Instant instant) throws IOException {
+        writeSecondsField(generator, fieldName, instant.toEpochMilli());
+    }
+
+    static void writeSecondsField(JsonGenerator generator, String fieldName, Duration duration) throws IOException {
+        writeSecondsField(generator, fieldName, duration.toMillis());
+    }
+
+    static void writeSecondsField(JsonGenerator generator, String fieldName, double seconds) throws IOException {
+        writeSecondsField(generator, fieldName, (long)(seconds * 1000));
+    }
+
+    static void writeSecondsField(JsonGenerator generator, String fieldName, long milliseconds) throws IOException {
+        generator.writeFieldName(fieldName);
+        generator.writeRawValue(toSecondsString(milliseconds));
+    }
+
+    /** @return a string with number of seconds with 3 decimals */
+    static String toSecondsString(long milliseconds) {
+        StringBuilder builder = new StringBuilder().append(milliseconds / 1000L).append('.');
+        long decimals = milliseconds % 1000;
+        if (decimals < 100) {
+            builder.append('0');
+            if (decimals < 10) {
+                builder.append('0');
+            }
+        }
+        return builder.append(decimals).toString();
+    }
+}