1 files changed, 118 insertions, 0 deletions
diff --git a/src/main/java/org/openslx/libvirt/domain/DomainUtils.java b/src/main/java/org/openslx/libvirt/domain/DomainUtils.java
new file mode 100644
index 0000000..2462371
--- /dev/null
+++ b/src/main/java/org/openslx/libvirt/domain/DomainUtils.java
@@ -0,0 +1,118 @@
+package org.openslx.libvirt.domain;
+
+import java.math.BigInteger;
+
+/**
+ * Collection of helper functions to maintain a Libvirt domain XML document.
+ * 
+ * @author Manuel Bentele
+ * @version 1.0
+ */
+public final class DomainUtils
+{
+
+	/**
+	 * Converts memory value with specified SI unit to absolute value in bytes.
+	 * 
+	 * @param value amount of memory in specified SI unit.
+	 * @param unit SI unit name, one of: bytes, KB, k, KiB, MB, M, MiB, GB, G, GiB, TB, T, TiB, for
+	 *           <code>value</code>.
+	 * @return absolute amount of memory in bytes.
+	 */
+	public static BigInteger decodeMemory( String value, String unit )
+	{
+		BigInteger factor = null;
+		BigInteger result = new BigInteger( value );
+
+		switch ( unit ) {
+		case "b":
+		case "bytes":
+			factor = new BigInteger( "1" );
+			break;
+		case "KB":
+			factor = new BigInteger( "1000" );
+			break;
+		case "k":
+		case "KiB":
+			factor = new BigInteger( "1024" );
+			break;
+		case "MB":
+			factor = new BigInteger( "1000000" );
+			break;
+		case "M":
+		case "MiB":
+			factor = new BigInteger( "1048576" );
+			break;
+		case "GB":
+			factor = new BigInteger( "1000000000" );
+			break;
+		case "G":
+		case "GiB":
+			factor = new BigInteger( "1073741824" );
+			break;
+		case "TB":
+			factor = new BigInteger( "1000000000000" );
+			break;
+		case "T":
+		case "TiB":
+			factor = new BigInteger( "1099511627776" );
+			break;
+		default:
+			return null;
+		}
+
+		return result.multiply( factor );
+	}
+
+	/**
+	 * Convert memory from absolute value in bytes to value in specified SI unit.
+	 * 
+	 * @param value absolute amount of memory in bytes.
+	 * @param unit SI unit name, one of: bytes, KB, k, KiB, MB, M, MiB, GB, G, GiB, TB, T, TiB for
+	 *           returned memory value.
+	 * @return amount of memory in specified SI unit.
+	 */
+	public static String encodeMemory( BigInteger value, String unit )
+	{
+		BigInteger dividend = null;
+
+		switch ( unit ) {
+		case "b":
+		case "bytes":
+			dividend = new BigInteger( "1" );
+			break;
+		case "KB":
+			dividend = new BigInteger( "1000" );
+			break;
+		case "k":
+		case "KiB":
+			dividend = new BigInteger( "1024" );
+			break;
+		case "MB":
+			dividend = new BigInteger( "1000000" );
+			break;
+		case "M":
+		case "MiB":
+			dividend = new BigInteger( "1048576" );
+			break;
+		case "GB":
+			dividend = new BigInteger( "1000000000" );
+			break;
+		case "G":
+		case "GiB":
+			dividend = new BigInteger( "1073741824" );
+			break;
+		case "TB":
+			dividend = new BigInteger( "1000000000000" );
+			break;
+		case "T":
+		case "TiB":
+			dividend = new BigInteger( "1099511627776" );
+			break;
+		default:
+			return null;
+		}
+
+		return value.divide( dividend ).toString();
+	}
+}