NullPointerException with devtools in 1.4.0.M2

[wangxufire]

Exception in thread "main" java.lang.NullPointerException
    at org.springframework.boot.devtools.restart.ChangeableUrls.getUrlsFromClassPathAttribute(ChangeableUrls.java:121)
    at org.springframework.boot.devtools.restart.ChangeableUrls.getUrlsFromClassPathOfJarManifestIfPossible(ChangeableUrls.java:99)
    at org.springframework.boot.devtools.restart.ChangeableUrls.fromUrlClassLoader(ChangeableUrls.java:88)
    at org.springframework.boot.devtools.restart.DefaultRestartInitializer.getUrls(DefaultRestartInitializer.java:91)
    at org.springframework.boot.devtools.restart.DefaultRestartInitializer.getInitialUrls(DefaultRestartInitializer.java:54)
    at org.springframework.boot.devtools.restart.Restarter.<init>(Restarter.java:133)
    at org.springframework.boot.devtools.restart.Restarter.initialize(Restarter.java:519)
    at org.springframework.boot.devtools.restart.RestartApplicationListener.onApplicationStartedEvent(RestartApplicationListener.java:68)
    at org.springframework.boot.devtools.restart.RestartApplicationListener.onApplicationEvent(RestartApplicationListener.java:45)
    at org.springframework.context.event.SimpleApplicationEventMulticaster.invokeListener(SimpleApplicationEventMulticaster.java:166)
    at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:138)
    at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:121)
    at org.springframework.boot.context.event.EventPublishingRunListener.publishEvent(EventPublishingRunListener.java:111)
    at org.springframework.boot.context.event.EventPublishingRunListener.started(EventPublishingRunListener.java:60)
    at org.springframework.boot.SpringApplicationRunListeners.started(SpringApplicationRunListeners.java:48)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:304)

worked correctly with 1.3.3.RELEASE

[wilkinsona]

The line in question is:

        String classPath = manifest.getMainAttributes()
                .getValue(Attributes.Name.CLASS_PATH);

manifest must be null (getMainAttributes will never return null), so I guess there's a jar on the classpath that doesn't have a META-INF/MANIFEST.MF.