io.nats.examples.ExampleArgs Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of jnats Show documentation
Show all versions of jnats Show documentation
Client library for working with the NATS messaging system.
// Copyright 2020 The NATS Authors
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at:
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package io.nats.examples;
import io.nats.client.Options;
import io.nats.client.impl.Headers;
public class ExampleArgs {
public enum Trail {MESSAGE, COUNT, QUEUE_AND_COUNT}
private String title;
public String server = Options.DEFAULT_URL;
public String subject;
public String queue;
public String message;
public int msgCount = Integer.MIN_VALUE;
public int msgSize = Integer.MIN_VALUE;
private boolean msgCountUnlimitedFlag;
public int subCount = Integer.MIN_VALUE;
public String stream;
public String mirror;
public String consumer;
public String durable;
public String deliverSubject;
public int pullSize = Integer.MIN_VALUE;
public Headers headers;
public boolean containedUnknown = false;
public String bucket;
public String description;
public boolean hasHeaders() {
return headers != null && headers.size() > 0;
}
private ExampleArgs(String title) {
this.title = title;
}
public ExampleArgs(String[] args, Trail trail, String usageString) {
parse(args, trail, usageString);
}
public void parse(String[] args, Trail trail, String usageString) {
try {
if (args != null) {
String lastKey = null;
for (int x = 0; x < args.length; x++) {
String arg = args[x];
if (arg.startsWith("-")) {
if (++x >= args.length) {
usageThenExit(usageString);
}
handleKeyedArg(arg, args[x]);
lastKey = arg;
}
else if (trail == null) {
if (lastKey != null) {
handleKeyedArg(lastKey, arg);
}
}
else {
handleTrailingArg(trail, arg);
lastKey = null;
}
}
}
} catch (RuntimeException e) {
System.err.println("Exception while processing command line arguments: " + e + "\n");
usageThenExit(usageString);
}
}
private void handleTrailingArg(Trail trail, String arg) {
if (subject == null) { // subject always the first expected
subject = arg;
}
else if (trail == Trail.MESSAGE) {
if (message == null) {
message = arg;
}
else {
message = message + " " + arg;
}
}
else if (trail == Trail.QUEUE_AND_COUNT) {
if (queue == null) {
queue = arg;
}
else {
msgCount = Integer.parseInt(arg);
}
}
else { // Expect.COUNT
msgCount = Integer.parseInt(arg);
}
}
private void handleKeyedArg(String key, String value) {
switch (key) {
case "-s":
server = value;
break;
case "-sub":
subject = value;
break;
case "-q":
queue = value;
break;
case "-m":
if (message == null) {
message = value;
}
else {
message = message + " " + value;
}
break;
case "-con":
consumer = value;
break;
case "-strm":
stream = value;
break;
case "-mir":
mirror = value;
break;
case "-pull":
pullSize = Integer.parseInt(value);
break;
case "-mcnt":
msgCount = Integer.parseInt(value);
break;
case "-msize":
msgSize = Integer.parseInt(value);
break;
case "-scnt":
subCount = Integer.parseInt(value);
break;
case "-dur":
durable = value;
break;
case "-buk":
bucket = value;
break;
case "-desc":
description = value;
break;
case "-deliver":
deliverSubject = value;
break;
case "-r":
if (headers == null) {
headers = new Headers();
}
String[] hdr = value.split(":");
headers.add(hdr[0], hdr[1]);
break;
default:
containedUnknown = true;
break;
}
}
public void displayBanner() {
if (title == null) {
System.out.println("\nExample");
}
else {
System.out.format("\n%s Example\n", title);
}
_banner("server", server);
_banner("stream", stream);
_banner("subject", subject);
_banner("bucket", bucket);
_banner("description", description);
_banner("queue", queue);
_banner("message", message);
_banner("mirror", mirror);
_banner("consumer", consumer);
_banner("durable", durable);
_banner("deliver", deliverSubject);
_banner("msgCount", msgCount, msgCountUnlimitedFlag);
_banner("msgSize", msgSize);
_banner("subCount", subCount);
_banner("pullSize", pullSize);
_banner("Headers", headers == null || headers.size() == 0 ? Integer.MIN_VALUE : headers.size());
System.out.println();
}
private void _banner(String label, String value) {
if (value != null) {
System.out.format(" %s: %s\n", label, value);
}
}
private void _banner(String label, int value) {
_banner(label, value, false);
}
private void _banner(String label, int value, boolean unlimited)
{
if (unlimited && (value == Integer.MAX_VALUE || value < 1)) {
System.out.format(" %s: Unlimited\n", label);
}
else if (value > Integer.MIN_VALUE) {
System.out.format(" %s: %s\n", label, value);
}
}
public static Builder builder(String title, String[] args, String usage) {
return new Builder(title, args, usage);
}
public static class Builder {
private final ExampleArgs ea;
private final String[] args;
private final String usage;
public Builder(String title, String[] args, String usage)
{
ea = new ExampleArgs(title);
this.args = args;
this.usage = usage;
}
public Builder defaultSubject(String subject) {
ea.subject = subject;
return this;
}
public Builder defaultQueue(String queue) {
ea.queue = queue;
return this;
}
public Builder defaultMessage(String message) {
ea.message = message;
return this;
}
public Builder defaultMsgCount(int msgCount) {
return defaultMsgCount(msgCount, false);
}
public Builder defaultMsgCount(int msgCount, boolean unlimitedFlag) {
ea.msgCount = msgCount;
ea.msgCountUnlimitedFlag = unlimitedFlag;
return this;
}
public Builder defaultMsgSize(int msgSize) {
ea.msgSize = msgSize;
return this;
}
public Builder defaultSubCount(int subCount) {
ea.subCount = subCount;
return this;
}
public Builder defaultStream(String stream) {
ea.stream = stream;
return this;
}
public Builder defaultMirror(String mirror) {
ea.mirror = mirror;
return this;
}
public Builder defaultDurable(String durable) {
ea.durable = durable;
return this;
}
public Builder defaultBucket(String bucket) {
ea.bucket = bucket;
return this;
}
public Builder defaultDescription(String description) {
ea.description = description;
return this;
}
public Builder defaultDeliverSubject(String deliver) {
ea.deliverSubject = deliver;
return this;
}
public Builder defaultPullSize(int pullSize) {
ea.pullSize = pullSize;
return this;
}
public ExampleArgs build() {
ea.parse(args, null, usage);
if (ea.containedUnknown && usage != null) {
usageThenExit(usage);
}
ea.displayBanner();
return ea;
}
}
private static void usageThenExit(String usageString) {
if (usageString != null) {
System.out.println(usageString);
}
System.exit(-1);
}
}© 2015 - 2025 Weber Informatics LLC | Privacy Policy