我在我的项目中使用 Jersey 和 Spring。 'jersey-spring3' 用于它们之间的集成。我想让我的资源类更灵活，并在 @Path 注释中使用属性，例如：
@Path("${some.property}/abc/def")
但是 Spring 不能将 some.property 注入 Jersey 的注解 @Path 和 @ApplicationPath。
有没有办法在 Jersey 资源的 @Path 值中设置一些可配置的（使用属性文件）值？
（我意识到用 Spring MVC 替换 Jersey 会更容易，但不幸的是我没有这个选择。）
【问题讨论】：
标签： java spring spring-mvc jersey jersey-2.0
所以这是答案的一半（或者可能是完整的答案，具体取决于解决 @ApplicationPath 对您的重要性）。
要了解以下解决方案，您应该首先了解一下 Jersey 的内部结构。当我们加载我们的应用程序时，Jersey 会构建所有资源的模型。资源的所有信息都封装在此模型中。 Jersey 使用此模型来处理请求，而不是尝试在每个请求上处理资源，将有关资源的所有信息保存在模型中并处理模型会更快。
通过这种架构，Jersey 还允许我们使用与内部用于保存模型属性的 API 相同的 API build resources programmatically。除了构建资源模型，我们还可以modify existing models，使用ModelProcessors。
在ModelProcessor 中，我们可以注入Spring 的PropertyResolver，然后以编程方式解析占位符，并将旧的资源模型路径替换为已解析的路径。例如
@Autowired
private PropertyResolver propertyResolver;
private ResourceModel processResourceModel(ResourceModel resourceModel) {
ResourceModel.Builder newResourceModelBuilder = new ResourceModel.Builder(false);
for (final Resource resource : resourceModel.getResources()) {
final Resource.Builder resourceBuilder = Resource.builder(resource);
String resolvedResourcePath = processPropertyPlaceholder(resource);
resourceBuilder.path(resolvedResourcePath);
// handle child resources
for (Resource childResource : resource.getChildResources()) {
String resolvedChildPath = processPropertyPlaceholder(childResource);
final Resource.Builder childResourceBuilder = Resource.builder(childResource);
childResourceBuilder.path(resolvedChildPath);
resourceBuilder.addChildResource(childResourceBuilder.build());
}
newResourceModelBuilder.addResource(resourceBuilder.build());
}
return newResourceModelBuilder.build();
}
private String processPropertyPlaceholder(Resource resource) {
String ogPath = resource.getPath();
return propertyResolver.resolvePlaceholders(ogPath);
}
就资源模型 API 而言
这是Resource
@Path("resource")
public class SomeResource {
@GET
public String get() {}
}
它没有注解@Path的资源方法是ResourceMethods
这是上述Resource 的子 Resource，因为它带有@Path 注释。
@GET
@Path("child-resource")
public String get() {}
这些信息应该让您对上述实现的工作原理有所了解。
下面是一个完整的测试，使用Jersey Test Framework。使用了以下类路径属性文件
app.properties
resource=resource
sub.resource=sub-resource
sub.resource.locator=sub-resource-locator
您可以像运行任何其他 JUnit 测试一样运行以下内容。
import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.core.Response;
import org.glassfish.jersey.filter.LoggingFilter;
import org.glassfish.jersey.server.ResourceConfig;
import org.glassfish.jersey.server.model.ModelProcessor;
import org.glassfish.jersey.server.model.Resource;
import org.glassfish.jersey.server.model.ResourceModel;
import org.glassfish.jersey.test.JerseyTest;
import org.junit.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.PropertySource;
import org.springframework.core.env.PropertyResolver;
import static org.hamcrest.CoreMatchers.equalTo;
import static org.hamcrest.CoreMatchers.is;
import static org.junit.Assert.assertThat;
/**
* Stack Overflow http://stackoverflow.com/q/34943650/2587435
*
* Run it like any other JUnit test. Required dependencies are as follows:
*
* <dependency>
* <groupId>org.glassfish.jersey.test-framework.providers</groupId>
* <artifactId>jersey-test-framework-provider-grizzly2</artifactId>
* <version>2.22.1</version>
* <scope>test</scope>
* </dependency>
* <dependency>
* <groupId>org.glassfish.jersey.ext</groupId>
* <artifactId>jersey-spring3</artifactId>
* <version>2.22.1</version>
* <scope>test</scope>
* </dependency>
* <dependency>
* <groupId>commons-logging</groupId>
* <artifactId>commons-logging</artifactId>
* <version>1.1</version>
* <scope>test</scope>
* </dependency>
*
* @author Paul Samsotha
*/
public class SpringPathResolverTest extends JerseyTest {
@Path("${resource}")
public static class TestResource {
@GET
public String get() {
return "Resource Success!";
}
@GET
@Path("${sub.resource}")
public String getSubMethod() {
return "Sub-Resource Success!";
}
@Path("${sub.resource.locator}")
public SubResourceLocator getSubResourceLocator() {
return new SubResourceLocator();
}
public static class SubResourceLocator {
@GET
public String get() {
return "Sub-Resource-Locator Success!";
}
}
}
@Configuration
@PropertySource("classpath:/app.properties")
public static class SpringConfig {
}
public static class PropertyPlaceholderPathResolvingModelProcessor
implements ModelProcessor {
@Autowired
private PropertyResolver propertyResolver;
@Override
public ResourceModel processResourceModel(ResourceModel resourceModel,
javax.ws.rs.core.Configuration configuration) {
return processResourceModel(resourceModel);
}
@Override
public ResourceModel processSubResource(ResourceModel subResourceModel,
javax.ws.rs.core.Configuration configuration) {
return subResourceModel;
}
private ResourceModel processResourceModel(ResourceModel resourceModel) {
ResourceModel.Builder newResourceModelBuilder = new ResourceModel.Builder(false);
for (final Resource resource : resourceModel.getResources()) {
final Resource.Builder resourceBuilder = Resource.builder(resource);
String resolvedResourcePath = processPropertyPlaceholder(resource);
resourceBuilder.path(resolvedResourcePath);
// handle child resources
for (Resource childResource : resource.getChildResources()) {
String resolvedChildPath = processPropertyPlaceholder(childResource);
final Resource.Builder childResourceBuilder = Resource.builder(childResource);
childResourceBuilder.path(resolvedChildPath);
resourceBuilder.addChildResource(childResourceBuilder.build());
}
newResourceModelBuilder.addResource(resourceBuilder.build());
}
return newResourceModelBuilder.build();
}
private String processPropertyPlaceholder(Resource resource) {
String ogPath = resource.getPath();
return propertyResolver.resolvePlaceholders(ogPath);
}
}
@Override
public ResourceConfig configure() {
ApplicationContext ctx = new AnnotationConfigApplicationContext(SpringConfig.class);
return new ResourceConfig(TestResource.class)
.property("contextConfig", ctx)
.register(PropertyPlaceholderPathResolvingModelProcessor.class)
.register(new LoggingFilter(Logger.getAnonymousLogger(), true));
}
@Test
public void pathPlaceholderShouldBeResolved() {
Response response = target("resource").request().get();
assertThat(response.getStatus(), is(200));
assertThat(response.readEntity(String.class), is(equalTo("Resource Success!")));
response.close();
response = target("resource/sub-resource").request().get();
assertThat(response.getStatus(), is(200));
assertThat(response.readEntity(String.class), is(equalTo("Sub-Resource Success!")));
response.close();
response = target("resource/sub-resource-locator").request().get();
assertThat(response.getStatus(), is(200));
assertThat(response.readEntity(String.class), is(equalTo("Sub-Resource-Locator Success!")));
response.close();
}
}
现在我想起来了，我可以看到一种使用解析@ApplicationPath 的方法，但它涉及创建 Jersey servlet 容器
以编程方式在 Spring WebAppInitializer 中。老实说，我认为这将比它的价值更麻烦。我只是把它吸起来，然后将@ApplicationPath 保留为静态字符串。
如果您使用的是 Spring boot，那么应用程序路径肯定是可配置的，通过 spring.jersey.applicationPath 属性。 Spring boot 加载 Jersey 的方式几乎就是我在上一段中想到的想法，您自己创建 Jersey servlet 容器，并设置 servlet 映射。这就是 Spring Boot 的配置方式。
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