org.glassfish.appclient.client.acc.UserError Maven / Gradle / Ivy
/*
* Copyright (c) 1997, 2018 Oracle and/or its affiliates. All rights reserved.
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v. 2.0, which is available at
* http://www.eclipse.org/legal/epl-2.0.
*
* This Source Code may also be made available under the following Secondary
* Licenses when the conditions for such availability set forth in the
* Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
* version 2 with the GNU Classpath Exception, which is available at
* https://www.gnu.org/software/classpath/license.html.
*
* SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
*/
package org.glassfish.appclient.client.acc;
import java.io.ByteArrayOutputStream;
import java.io.PrintStream;
import java.text.MessageFormat;
/**
*Represents any user error, such as an invalid combination of command options,
*or specifying a non-existent JAR file.
*
*Such errors should be user-correctable, provided the message is clear.
*So no stack traces should be displayed when UserErrors are thrown.
*
* @author tjquinn
*/
public class UserError extends Throwable {
/** Allows user to turn on stack traces for user errors - normally off */
private static final String SHOW_STACK_TRACES_PROPERTY_NAME =
UserError.class.getPackage().getName() + ".showUserErrorStackTraces";
/**
* Creates a new UserError instance having formatted the message with the
* arguments provided.
*@param message the message string, presumably containing argument placeholders
*@param args 0 or more arguments for substitution for the placeholders in the message string
*@return new UserError with message formatted as requested
*/
public static UserError formatUserError(String message, String... args) {
String formattedMessage = MessageFormat.format(message, (Object[]) args);
UserError ue = new UserError(formattedMessage);
return ue;
}
/** xmlMessage implementation showed the usage message after the error */
private String usage = null;
public UserError(String message) {
super(message);
}
public UserError(String message, Throwable cause) {
super(message, cause);
}
public UserError(Throwable cause) {
super(cause);
}
/**
*Sets whether or not the usage message should be displayed after the
*error message is displayed to the user.
*@param showUsage the new setting
*/
public void setUsage(String usage) {
this.usage = usage;
}
/**
*Displays the user error message, and any messages along the exception
*chain, if any, and then exits. If showUsage has been set to true, then
*the usage message is displayed before exiting.
*
*Only the messages, and not the stack traces, are shown because these are
*user errors that should be user-correctable. Stack traces are too
*alarming and of minimal use to the user as he or she tries to understand
*and fix the error.
*/
public void displayAndExit() {
display(System.err);
System.exit(1);
}
private void display(final PrintStream ps) {
for (Throwable t = this; t != null; t = t.getCause()) {
ps.println(t.toString());
}
if (usage != null) {
ps.println(usage);
}
if (Boolean.getBoolean(SHOW_STACK_TRACES_PROPERTY_NAME)) {
printStackTrace(ps);
}
}
public String messageForGUIDisplay() {
ByteArrayOutputStream os = new ByteArrayOutputStream();
PrintStream ps = new PrintStream(os);
display(ps);
return os.toString();
}
}