RequestReferences.java

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package com.techempower.gemini.path;

import com.techempower.gemini.*;

/**
 * Provides ThreadLocal access to key references that exist for the lifetime
 * of a request.
 */
public class RequestReferences
{
  
  private final static ThreadLocal<RequestReferences> MAP = new ThreadLocal<>();

  /**
   * The current request context.
   */
  public final Context context;
  
  /**
   * The request URI segments.
   */
  public final PathSegments segments;
  
  /**
   * The specified template, which is optional.  Typical behavior is for
   * rendering to use the defaultTemplate if template is null.
   */
  public String template;
  
  /**
   * A default template to use if template is null.  This is typically not
   * set by application code, but rather by the framework itself.
   */
  public String defaultTemplate;
  
  /**
   * Gets the template, using the defaultTemplate if the specific template is
   * null.  Note that defaultTemplate may also be null, so it is possible for
   * this method to return null.
   */
  public String getTemplate()
  {
    return (template != null ? template : defaultTemplate);
  }
  
  private RequestReferences(Context context, PathSegments segments)
  {
    this.context = context;
    this.segments = segments;
  }
  
  /**
   * Gets the current thread's references.
   */
  public static RequestReferences get()
  {
    return MAP.get();
  }

  /**
   * Sets the current thread's references.
   */
  public static RequestReferences set(Context context, PathSegments segments)
  {
    final RequestReferences refs = new RequestReferences(context, segments); 
    MAP.set(refs);
    return refs;
  }
  
  /**
   * Clears the current thread's references.
   */
  public static void remove()
  {
    MAP.remove();
  }
  
}