Java Optional类代码示例

import org.jvnet.hk2.annotations.Optional; //导入依赖的package包/类
@Inject
public VelocityDefaultConfigurationFactory(@Optional final ServletContext servletContext) {
    String loader = "class";
    Velocity.setProperty("class.resource.loader.class", ClasspathResourceLoader.class.getName());
    Velocity.setProperty(RuntimeConstants.FILE_RESOURCE_LOADER_CACHE, "true");

    if (servletContext != null) {
        Velocity.setProperty("webapp.resource.loader.class", WebappResourceLoader.class.getName());
        Velocity.setProperty("webapp.resource.loader.path", "/");
        Velocity.setApplicationAttribute("javax.servlet.ServletContext", servletContext);
        loader += ",webapp";
    }
    Velocity.setProperty(RuntimeConstants.RESOURCE_LOADER, loader);

    configuration = new Configuration();
}
 

import org.jvnet.hk2.annotations.Optional; //导入依赖的package包/类
@Inject
public VelocityViewProcessor(final javax.ws.rs.core.Configuration config, final ServiceLocator serviceLocator,
                             @Optional final ServletContext servletContext) {
    super(config, servletContext, "velocity", "vm");

    this.factory = getTemplateObjectFactory(serviceLocator, VelocityConfigurationFactory.class,
            new Value<VelocityConfigurationFactory>() {
                @Override
                public VelocityConfigurationFactory get() {
                    Configuration configuration = getTemplateObjectFactory(serviceLocator, Configuration.class,
                            Values.<Configuration>empty());
                    if (configuration == null) {
                        return new VelocityDefaultConfigurationFactory(servletContext);
                    } else {
                        return new VelocitySuppliedConfigurationFactory(configuration);
                    }
                }
            });
    Velocity.init();
}
 

import org.jvnet.hk2.annotations.Optional; //导入依赖的package包/类
/**
 * Create an instance of this processor with injected {@link javax.ws.rs.core.Configuration config} and
 * (optional) {@link javax.servlet.ServletContext servlet context}.
 *
 * @param config         config to configure this processor from.
 * @param serviceLocator service locator to initialize template object factory if needed.
 * @param servletContext (optional) servlet context to obtain template resources from.
 */
@Inject
public FreemarkerViewProcessor(final javax.ws.rs.core.Configuration config, final ServiceLocator serviceLocator,
                               @Optional final ServletContext servletContext) {
    super(config, servletContext, "freemarker", getSupportedExtensions(config, servletContext));

    this.factory = getTemplateObjectFactory(serviceLocator, FreemarkerConfigurationFactory.class,
            new Value<FreemarkerConfigurationFactory>() {
                @Override
                public FreemarkerConfigurationFactory get() {
                    Configuration configuration = getTemplateObjectFactory(serviceLocator, Configuration.class,
                            Values.<Configuration>empty());
                    if (configuration == null) {
                        return new FreemarkerDefaultConfigurationFactory(servletContext);
                    } else {
                        return new FreemarkerSuppliedConfigurationFactory(configuration);
                    }
                }
            });

}
 

import org.jvnet.hk2.annotations.Optional; //导入依赖的package包/类
@Inject
public FlexibleConfiguration(final javax.ws.rs.core.Configuration config, @Optional final ServletContext servletContext) {
    super();

    final List<TemplateLoader> loaders = new ArrayList<>();
    if (servletContext != null) {
        loaders.add(new WebappTemplateLoader(servletContext));
    }
    loaders.add(new ClassTemplateLoader(FlexibleConfiguration.class, "/"));

    // Create Factory.
    this.setTemplateLoader(new MultiTemplateLoader(loaders.toArray(new TemplateLoader[loaders.size()])));
    try {
        settingConfiguration(config);
    } catch (TemplateException e) {
        throw new RuntimeException(e);
    }
}
 

import org.jvnet.hk2.annotations.Optional; //导入依赖的package包/类
@Inject
public UserTokenFilter(
        TokenServiceClient tokenServiceClient,
        UserTokenFilterAddon configuration,
        @Optional UserTokenAuthenticatedHandler authenticatedHandler)
{
    this.tokenServiceClient = tokenServiceClient;
    this.configuration = configuration;
    this.authenticatedHandler = authenticatedHandler;
}
 

import org.jvnet.hk2.annotations.Optional; //导入依赖的package包/类
@Inject
public TaggedMetricRegistry(
    @NonNull MetricRegistry registry, @NonNull @Optional Provider<MetricNameService> metricNameServiceProvider
) {
    this.delegate = registry;
    this.metricNameServiceProvider = metricNameServiceProvider;
}
 

import org.jvnet.hk2.annotations.Optional; //导入依赖的package包/类
@Inject
public ClientNameFilter(@Named(CLIENT_APPNAME) @Optional String clientAppName) {
    this.clientAppName = clientAppName;
}
 

import org.jvnet.hk2.annotations.Optional; //导入依赖的package包/类
@Inject
public DefaultMetricNameService(@NonNull IterableProvider<MetricNameFilter> filters, @Optional MetricNameFormatter formatter) {
    this.filters = filters;
    this.formatter = formatter == null ? new DefaultMetricNameFormatter() : formatter;
}
 

import org.jvnet.hk2.annotations.Optional; //导入依赖的package包/类
public BeanParamModel(@PathParam("path-value") @Optional String pathValue,
		@QueryParam("param1") @Optional String param1) {
	this.pathValue = pathValue;
	this.param1 = param1;
}