5373 add exception class with user friendly exception

Core/src/org/sleuthkit/autopsy/exceptions/AutopsyException.java

@@ -0,0 +1,65 @@
+/*
+ * To change this license header, choose License Headers in Project Properties.
+ * To change this template file, choose Tools | Templates
+ * and open the template in the editor.
+ */
+package org.sleuthkit.autopsy.exceptions;
+
+public abstract class AutopsyException extends Exception {
+
+    private static final long serialVersionUID = 1L;
+
+    private String userMessage = "";
+
+    /**
+     * Constructs an exception to be thrown by a autopsy without a user message.
+     *
+     * @param message Exception message.
+     */
+    public AutopsyException(String message) {
+        super(message);
+    }
+
+    /**
+     * Constructs an exception to be thrown by a autopsy with a user exception.
+     *
+     * @param message     Exception message.
+     * @param userMessage the user friendly message to include in this exception
+     */
+    public AutopsyException(String message, String userMessage) {
+        super(message);
+        this.userMessage = userMessage;
+    }
+
+    /**
+     * Constructs an exception to be thrown by a autopsy without a user message.
+     *
+     * @param message Exception message.
+     * @param cause   Exception cause.
+     */
+    public AutopsyException(String message, Throwable cause) {
+        super(message, cause);
+    }
+
+    /**
+     * Constructs an exception to be thrown by a autopsy with a user exception.
+     *
+     * @param message     Exception message.
+     * @param userMessage the user friendly message to include in this exception
+     * @param cause       Exception cause.
+     */
+    public AutopsyException(String message, String userMessage, Throwable cause) {
+        super(message, cause);
+        this.userMessage = userMessage;
+    }
+
+    /**
+     * Get the user friendly message if one exists.
+     *
+     * @return the user friendly message if one exists, otherwise an empty String
+     */
+    public String getUserMessage() {
+        return userMessage;
+    }
+
+}