From 94b0dd4f5a381c0e7ac7cd155335b3cbff882386 Mon Sep 17 00:00:00 2001
From: Robert von Burg <eitch@eitchnet.ch>
Date: Tue, 18 Dec 2018 14:33:29 +0100
Subject: [PATCH] [New] Added XmlHelper.parseAndUnmarshalFile()

---
 .../li/strolch/utils/helper/XmlHelper.java    | 34 +++++++++++++++++++
 1 file changed, 34 insertions(+)

diff --git a/li.strolch.utils/src/main/java/li/strolch/utils/helper/XmlHelper.java b/li.strolch.utils/src/main/java/li/strolch/utils/helper/XmlHelper.java
index 0bab0fc6c..68a19836f 100644
--- a/li.strolch.utils/src/main/java/li/strolch/utils/helper/XmlHelper.java
+++ b/li.strolch.utils/src/main/java/li/strolch/utils/helper/XmlHelper.java
@@ -15,6 +15,9 @@
  */
 package li.strolch.utils.helper;
 
+import javax.xml.bind.JAXBContext;
+import javax.xml.bind.Unmarshaller;
+import javax.xml.bind.annotation.XmlRootElement;
 import javax.xml.parsers.*;
 import javax.xml.transform.OutputKeys;
 import javax.xml.transform.Source;
@@ -129,6 +132,37 @@ public class XmlHelper {
 		}
 	}
 
+	/**
+	 * <p>Helper method to parse the given {@link File} using JAXB to the given object type</p>
+	 *
+	 * <p><b>Note:</b> The passed class must have the {@link XmlRootElement} annotation!</p>
+	 *
+	 * @param file
+	 * 		the file to parse
+	 * @param clazz
+	 * 		the class for the returning object type
+	 * @param <T>
+	 * 		the type of object to return
+	 *
+	 * @return the parsed object
+	 */
+	public static <T> T parseAndUnmarshalFile(File file, Class<T> clazz) {
+		try (FileInputStream fin = new FileInputStream(file)) {
+
+			JAXBContext jaxbContext = JAXBContext.newInstance(clazz);
+			Unmarshaller unmarshaller = jaxbContext.createUnmarshaller();
+
+			@SuppressWarnings("unchecked")
+			T o = (T) unmarshaller.unmarshal(fin);
+
+			return o;
+
+		} catch (Exception e) {
+			throw new IllegalStateException("Failed to parse file " + file.getAbsolutePath() + " to object " + clazz,
+					e);
+		}
+	}
+
 	/**
 	 * Writes an {@link Element} to an XML file on the file system
 	 *