HTTPCLIENT-2277: optimization of internal cache operations

httpclient5-cache/src/main/java/org/apache/hc/client5/http/cache/HeaderConstants.java

@@ -33,12 +33,40 @@
  */
 public class HeaderConstants {
 
+    /**
+     * @deprecated Use {@link org.apache.hc.core5.http.Method}
+     */
+    @Deprecated
     public static final String GET_METHOD = "GET";
+    /**
+     * @deprecated Use {@link org.apache.hc.core5.http.Method}
+     */
+    @Deprecated
     public static final String HEAD_METHOD = "HEAD";
+    /**
+     * @deprecated Use {@link org.apache.hc.core5.http.Method}
+     */
+    @Deprecated
     public static final String OPTIONS_METHOD = "OPTIONS";
+    /**
+     * @deprecated Use {@link org.apache.hc.core5.http.Method}
+     */
+    @Deprecated
     public static final String PUT_METHOD = "PUT";
+    /**
+     * @deprecated Use {@link org.apache.hc.core5.http.Method}
+     */
+    @Deprecated
     public static final String DELETE_METHOD = "DELETE";
+    /**
+     * @deprecated Use {@link org.apache.hc.core5.http.Method}
+     */
+    @Deprecated
     public static final String TRACE_METHOD = "TRACE";
+    /**
+     * @deprecated Use {@link org.apache.hc.core5.http.Method}
+     */
+    @Deprecated
     public static final String POST_METHOD = "POST";
 
     /**

httpclient5-cache/src/main/java/org/apache/hc/client5/http/impl/cache/CacheHit.java

@@ -0,0 +1,60 @@
+/*
+ * ====================================================================
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ *
+ */
+package org.apache.hc.client5.http.impl.cache;
+
+import org.apache.hc.client5.http.cache.HttpCacheEntry;
+
+class CacheHit {
+
+    final String rootKey;
+    final String variantKey;
+    final HttpCacheEntry entry;
+
+    public CacheHit(final String rootKey, final String variantKey, final HttpCacheEntry entry) {
+        this.rootKey = rootKey;
+        this.variantKey = variantKey;
+        this.entry = entry;
+    }
+
+    public CacheHit(final String rootKey, final HttpCacheEntry entry) {
+        this(rootKey, null, entry);
+    }
+
+    public String getEntryKey() {
+        return variantKey != null ? variantKey : rootKey;
+    }
+
+    @Override
+    public String toString() {
+        return "CacheHit{" +
+                "rootKey='" + rootKey + '\'' +
+                ", variantKey='" + variantKey + '\'' +
+                ", entry=" + entry +
+                '}';
+    }
+
+}

httpclient5-cache/src/main/java/org/apache/hc/client5/http/impl/cache/CacheInvalidatorBase.java

@@ -28,13 +28,13 @@
 
 import java.net.URI;
 
-import org.apache.hc.client5.http.cache.HeaderConstants;
 import org.apache.hc.client5.http.cache.HttpCacheEntry;
 import org.apache.hc.client5.http.utils.URIUtils;
 import org.apache.hc.core5.http.Header;
 import org.apache.hc.core5.http.HttpHeaders;
 import org.apache.hc.core5.http.HttpRequest;
 import org.apache.hc.core5.http.HttpResponse;
+import org.apache.hc.core5.http.Method;
 
 class CacheInvalidatorBase {
 
@@ -43,11 +43,11 @@ static boolean shouldInvalidateHeadCacheEntry(final HttpRequest req, final HttpC
     }
 
     static boolean requestIsGet(final HttpRequest req) {
-        return req.getMethod().equals((HeaderConstants.GET_METHOD));
+        return Method.GET.isSame(req.getMethod());
     }
 
     static boolean isAHeadCacheEntry(final HttpCacheEntry parentCacheEntry) {
-        return parentCacheEntry != null && parentCacheEntry.getRequestMethod().equals(HeaderConstants.HEAD_METHOD);
+        return parentCacheEntry != null && Method.HEAD.isSame(parentCacheEntry.getRequestMethod());
     }
 
     static boolean isSameHost(final URI requestURI, final URI targetURI) {
@@ -60,7 +60,7 @@ static boolean requestShouldNotBeCached(final HttpRequest req) {
     }
 
     static boolean notGetOrHeadRequest(final String method) {
-        return !(HeaderConstants.GET_METHOD.equals(method) || HeaderConstants.HEAD_METHOD.equals(method));
+        return !(Method.GET.isSame(method) || Method.HEAD.isSame(method));
     }
 
     private static URI getLocationURI(final URI requestUri, final HttpResponse response, final String headerName) {

httpclient5-cache/src/main/java/org/apache/hc/client5/http/impl/cache/Variant.java → httpclient5-cache/src/main/java/org/apache/hc/client5/http/impl/cache/CacheMatch.java

@@ -26,30 +26,26 @@
  */
 package org.apache.hc.client5.http.impl.cache;
 
-import org.apache.hc.client5.http.cache.HttpCacheEntry;
-
-/** Records a set of information describing a cached variant. */
-class Variant {
-
-    private final String cacheKey;
-    private final HttpCacheEntry entry;
-
-    public Variant(final String cacheKey, final HttpCacheEntry entry) {
-        this.cacheKey = cacheKey;
-        this.entry = entry;
-    }
+/**
+ * Represents a full match or a partial match (variant options)
+ * result of a cache lookup operation.
+ */
+class CacheMatch {
 
-    public String getCacheKey() {
-        return cacheKey;
-    }
+    final CacheHit hit;
+    final CacheHit root;
 
-    public HttpCacheEntry getEntry() {
-        return entry;
+    CacheMatch(final CacheHit hit, final CacheHit root) {
+        this.hit = hit;
+        this.root = root;
     }
 
     @Override
     public String toString() {
-        return cacheKey;
+        return "CacheLookupResult{" +
+                "hit=" + hit +
+                ", root=" + root +
+                '}';
     }
 
 }

httpclient5-cache/src/main/java/org/apache/hc/client5/http/impl/cache/CacheableRequestPolicy.java

@@ -26,10 +26,10 @@
  */
 package org.apache.hc.client5.http.impl.cache;
 
-import org.apache.hc.client5.http.cache.HeaderConstants;
 import org.apache.hc.core5.http.HttpHeaders;
 import org.apache.hc.core5.http.HttpRequest;
 import org.apache.hc.core5.http.HttpVersion;
+import org.apache.hc.core5.http.Method;
 import org.apache.hc.core5.http.ProtocolVersion;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -57,7 +57,7 @@ public boolean isServableFromCache(final RequestCacheControl cacheControl, final
             return false;
         }
 
-        if (!method.equals(HeaderConstants.GET_METHOD) && !method.equals(HeaderConstants.HEAD_METHOD)) {
+        if (!Method.GET.isSame(method) && !Method.HEAD.isSame(method)) {
             if (LOG.isDebugEnabled()) {
                 LOG.debug("{} request is not serveable from cache", method);
             }

httpclient5-cache/src/main/java/org/apache/hc/client5/http/impl/cache/CachedHttpResponseGenerator.java

@@ -29,7 +29,6 @@
 import java.time.Instant;
 
 import org.apache.hc.client5.http.async.methods.SimpleHttpResponse;
-import org.apache.hc.client5.http.cache.HeaderConstants;
 import org.apache.hc.client5.http.cache.HttpCacheEntry;
 import org.apache.hc.client5.http.cache.Resource;
 import org.apache.hc.client5.http.cache.ResourceIOException;
@@ -41,6 +40,7 @@
 import org.apache.hc.core5.http.HttpResponse;
 import org.apache.hc.core5.http.HttpStatus;
 import org.apache.hc.core5.http.HttpVersion;
+import org.apache.hc.core5.http.Method;
 import org.apache.hc.core5.http.message.BasicHeader;
 import org.apache.hc.core5.util.TimeValue;
 
@@ -64,7 +64,7 @@ class CachedHttpResponseGenerator {
      * @return {@link SimpleHttpResponse} constructed response
      */
     SimpleHttpResponse generateResponse(final HttpRequest request, final HttpCacheEntry entry) throws ResourceIOException {
-        final Instant now =Instant.now();
+        final Instant now = Instant.now();
         final SimpleHttpResponse response = new SimpleHttpResponse(entry.getStatus());
         response.setVersion(HttpVersion.DEFAULT);
 
@@ -160,7 +160,7 @@ private void generateContentLength(final HttpResponse response, final byte[] bod
     }
 
     private boolean responseShouldContainEntity(final HttpRequest request, final HttpCacheEntry cacheEntry) {
-        return request.getMethod().equals(HeaderConstants.GET_METHOD) && cacheEntry.getResource() != null;
+        return Method.GET.isSame(request.getMethod()) && cacheEntry.getResource() != null;
     }
 
     /**

httpclient5-cache/src/main/java/org/apache/hc/client5/http/impl/cache/CachedResponseSuitabilityChecker.java

@@ -29,14 +29,14 @@
 import java.time.Instant;
 import java.util.Iterator;
 
-import org.apache.hc.client5.http.cache.HeaderConstants;
 import org.apache.hc.client5.http.cache.HttpCacheEntry;
 import org.apache.hc.client5.http.utils.DateUtils;
 import org.apache.hc.core5.http.Header;
 import org.apache.hc.core5.http.HeaderElement;
 import org.apache.hc.core5.http.HttpHeaders;
 import org.apache.hc.core5.http.HttpRequest;
 import org.apache.hc.core5.http.HttpStatus;
+import org.apache.hc.core5.http.Method;
 import org.apache.hc.core5.http.message.MessageSupport;
 import org.apache.hc.core5.util.TimeValue;
 import org.slf4j.Logger;
@@ -176,7 +176,11 @@ public boolean canCachedResponseBeUsed(final RequestCacheControl requestCacheCon
     }
 
     private boolean isGet(final HttpRequest request) {
-        return request.getMethod().equals(HeaderConstants.GET_METHOD);
+        return Method.GET.isSame(request.getMethod());
+    }
+
+    private boolean isHead(final HttpRequest request) {
+        return Method.HEAD.isSame(request.getMethod());
     }
 
     private boolean entryIsNotA204Response(final HttpCacheEntry entry) {
@@ -201,17 +205,18 @@ public boolean isConditional(final HttpRequest request) {
     }
 
     /**
-     * Determines whether the given request is a {@link HeaderConstants#GET_METHOD} request and the associated cache entry was created by a
-     * {@link HeaderConstants#HEAD_METHOD} request.
+     * Determines whether the given request is a {@link org.apache.hc.core5.http.Method#GET} request and the
+     * associated cache entry was created by a {@link org.apache.hc.core5.http.Method#HEAD} request.
      *
-     * @param request The {@link HttpRequest} to check if it is a {@link HeaderConstants#GET_METHOD} request.
-     * @param entry   The {@link HttpCacheEntry} to check if it was created by a {@link HeaderConstants#HEAD_METHOD} request.
-     * @return true if the request is a {@link HeaderConstants#GET_METHOD} request and the cache entry was created by a
-     * {@link HeaderConstants#HEAD_METHOD} request, otherwise {@code false}.
+     * @param request The {@link HttpRequest} to check if it is a {@link org.apache.hc.core5.http.Method#GET} request.
+     * @param entry   The {@link HttpCacheEntry} to check if it was created by
+     *                a {@link org.apache.hc.core5.http.Method#HEAD} request.
+     * @return true if the request is a {@link org.apache.hc.core5.http.Method#GET} request and the cache entry was
+     * created by a {@link org.apache.hc.core5.http.Method#HEAD} request, otherwise {@code false}.
      * @since 5.3
      */
     public boolean isGetRequestWithHeadCacheEntry(final HttpRequest request, final HttpCacheEntry entry) {
-        return isGet(request) && HeaderConstants.HEAD_METHOD.equalsIgnoreCase(entry.getRequestMethod());
+        return isGet(request) && Method.HEAD.isSame(entry.getRequestMethod());
     }