avoid using streams API when transforming the headers list

open-telemetry · Oct 4, 2021 · 1e81792 · 1e81792
1 parent 1914320
commit 1e81792
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Showing 10 changed files with 110 additions and 56 deletions.
diff --git a/...t/instrumentation/apachehttpasyncclient/ApacheHttpAsyncClientHttpAttributesExtractor.java b/...t/instrumentation/apachehttpasyncclient/ApacheHttpAsyncClientHttpAttributesExtractor.java
@@ -5,12 +5,11 @@
 
 package io.opentelemetry.javaagent.instrumentation.apachehttpasyncclient;
 
+import static io.opentelemetry.javaagent.instrumentation.apachehttpasyncclient.ApacheHttpClientRequest.headersToList;
+
 import io.opentelemetry.instrumentation.api.instrumenter.http.HttpClientAttributesExtractor;
 import io.opentelemetry.javaagent.instrumentation.api.config.HttpHeadersConfig;
-import java.util.Arrays;
 import java.util.List;
-import java.util.stream.Collectors;
-import org.apache.http.Header;
 import org.apache.http.HttpResponse;
 import org.apache.http.StatusLine;
 import org.checkerframework.checker.nullness.qual.Nullable;
@@ -80,8 +79,6 @@ protected Long responseContentLengthUncompressed(
   @Override
   protected List<String> responseHeader(
       ApacheHttpClientRequest request, HttpResponse response, String name) {
-    return Arrays.stream(response.getHeaders(name))
-        .map(Header::getValue)
-        .collect(Collectors.toList());
+    return headersToList(response.getHeaders(name));
   }
 }
diff --git a/...pentelemetry/javaagent/instrumentation/apachehttpasyncclient/ApacheHttpClientRequest.java b/...pentelemetry/javaagent/instrumentation/apachehttpasyncclient/ApacheHttpClientRequest.java
@@ -8,9 +8,9 @@
 import io.opentelemetry.semconv.trace.attributes.SemanticAttributes;
 import java.net.URI;
 import java.net.URISyntaxException;
-import java.util.Arrays;
+import java.util.ArrayList;
+import java.util.Collections;
 import java.util.List;
-import java.util.stream.Collectors;
 import org.apache.http.Header;
 import org.apache.http.HttpHost;
 import org.apache.http.HttpRequest;
@@ -38,9 +38,19 @@ public ApacheHttpClientRequest(HttpHost httpHost, HttpRequest httpRequest) {
   }
 
   public List<String> getHeader(String name) {
-    return Arrays.stream(delegate.getHeaders(name))
-        .map(Header::getValue)
-        .collect(Collectors.toList());
+    return headersToList(delegate.getHeaders(name));
+  }
+
+  // minimize memory overhead by not using streams
+  static List<String> headersToList(Header[] headers) {
+    if (headers.length == 0) {
+      return Collections.emptyList();
+    }
+    List<String> headersList = new ArrayList<>(headers.length);
+    for (int i = 0; i < headers.length; ++i) {
+      headersList.set(i, headers[i].getValue());
+    }
+    return headersList;
   }
 
   public void setHeader(String name, String value) {

diff --git a/...aagent/instrumentation/apachehttpclient/v4_0/ApacheHttpClientHttpAttributesExtractor.java b/...aagent/instrumentation/apachehttpclient/v4_0/ApacheHttpClientHttpAttributesExtractor.java
@@ -5,12 +5,11 @@
 
 package io.opentelemetry.javaagent.instrumentation.apachehttpclient.v4_0;
 
+import static io.opentelemetry.javaagent.instrumentation.apachehttpclient.v4_0.ApacheHttpClientRequest.headersToList;
+
 import io.opentelemetry.instrumentation.api.instrumenter.http.HttpClientAttributesExtractor;
 import io.opentelemetry.javaagent.instrumentation.api.config.HttpHeadersConfig;
-import java.util.Arrays;
 import java.util.List;
-import java.util.stream.Collectors;
-import org.apache.http.Header;
 import org.apache.http.HttpResponse;
 import org.checkerframework.checker.nullness.qual.Nullable;
 
@@ -77,8 +76,6 @@ protected Long responseContentLengthUncompressed(
   @Override
   protected List<String> responseHeader(
       ApacheHttpClientRequest request, HttpResponse response, String name) {
-    return Arrays.stream(response.getHeaders(name))
-        .map(Header::getValue)
-        .collect(Collectors.toList());
+    return headersToList(response.getHeaders(name));
   }
 }
diff --git a/...pentelemetry/javaagent/instrumentation/apachehttpclient/v4_0/ApacheHttpClientRequest.java b/...pentelemetry/javaagent/instrumentation/apachehttpclient/v4_0/ApacheHttpClientRequest.java
@@ -8,9 +8,9 @@
 import io.opentelemetry.semconv.trace.attributes.SemanticAttributes;
 import java.net.URI;
 import java.net.URISyntaxException;
-import java.util.Arrays;
+import java.util.ArrayList;
+import java.util.Collections;
 import java.util.List;
-import java.util.stream.Collectors;
 import org.apache.http.Header;
 import org.apache.http.HttpHost;
 import org.apache.http.HttpRequest;
@@ -44,9 +44,19 @@ public ApacheHttpClientRequest(HttpUriRequest httpRequest) {
   }
 
   public List<String> getHeader(String name) {
-    return Arrays.stream(delegate.getHeaders(name))
-        .map(Header::getValue)
-        .collect(Collectors.toList());
+    return headersToList(delegate.getHeaders(name));
+  }
+
+  // minimize memory overhead by not using streams
+  static List<String> headersToList(Header[] headers) {
+    if (headers.length == 0) {
+      return Collections.emptyList();
+    }
+    List<String> headersList = new ArrayList<>(headers.length);
+    for (int i = 0; i < headers.length; ++i) {
+      headersList.set(i, headers[i].getValue());
+    }
+    return headersList;
   }
 
   public void setHeader(String name, String value) {

diff --git a/...emetry/instrumentation/apachehttpclient/v4_3/ApacheHttpClientHttpAttributesExtractor.java b/...emetry/instrumentation/apachehttpclient/v4_3/ApacheHttpClientHttpAttributesExtractor.java
@@ -5,12 +5,11 @@
 
 package io.opentelemetry.instrumentation.apachehttpclient.v4_3;
 
+import static io.opentelemetry.instrumentation.apachehttpclient.v4_3.ApacheHttpClientRequest.headersToList;
+
 import io.opentelemetry.instrumentation.api.instrumenter.http.CapturedHttpHeaders;
 import io.opentelemetry.instrumentation.api.instrumenter.http.HttpClientAttributesExtractor;
-import java.util.Arrays;
 import java.util.List;
-import java.util.stream.Collectors;
-import org.apache.http.Header;
 import org.apache.http.HttpResponse;
 import org.checkerframework.checker.nullness.qual.Nullable;
 
@@ -79,8 +78,6 @@ protected Long responseContentLengthUncompressed(
   @Override
   protected List<String> responseHeader(
       ApacheHttpClientRequest request, HttpResponse response, String name) {
-    return Arrays.stream(response.getHeaders(name))
-        .map(Header::getValue)
-        .collect(Collectors.toList());
+    return headersToList(response.getHeaders(name));
   }
 }
diff --git a/.../java/io/opentelemetry/instrumentation/apachehttpclient/v4_3/ApacheHttpClientRequest.java b/.../java/io/opentelemetry/instrumentation/apachehttpclient/v4_3/ApacheHttpClientRequest.java
@@ -8,9 +8,9 @@
 import io.opentelemetry.semconv.trace.attributes.SemanticAttributes;
 import java.net.URI;
 import java.net.URISyntaxException;
-import java.util.Arrays;
+import java.util.ArrayList;
+import java.util.Collections;
 import java.util.List;
-import java.util.stream.Collectors;
 import org.apache.http.Header;
 import org.apache.http.HttpHost;
 import org.apache.http.HttpRequest;
@@ -43,9 +43,19 @@ public HttpRequest getDelegate() {
   }
 
   List<String> getHeader(String name) {
-    return Arrays.stream(delegate.getHeaders(name))
-        .map(Header::getValue)
-        .collect(Collectors.toList());
+    return headersToList(delegate.getHeaders(name));
+  }
+
+  // minimize memory overhead by not using streams
+  static List<String> headersToList(Header[] headers) {
+    if (headers.length == 0) {
+      return Collections.emptyList();
+    }
+    List<String> headersList = new ArrayList<>(headers.length);
+    for (int i = 0; i < headers.length; ++i) {
+      headersList.set(i, headers[i].getValue());
+    }
+    return headersList;
   }
 
   void setHeader(String name, String value) {

diff --git a/...aagent/instrumentation/apachehttpclient/v5_0/ApacheHttpClientHttpAttributesExtractor.java b/...aagent/instrumentation/apachehttpclient/v5_0/ApacheHttpClientHttpAttributesExtractor.java
@@ -8,9 +8,9 @@
 import io.opentelemetry.instrumentation.api.instrumenter.http.HttpClientAttributesExtractor;
 import io.opentelemetry.javaagent.instrumentation.api.config.HttpHeadersConfig;
 import io.opentelemetry.semconv.trace.attributes.SemanticAttributes;
-import java.util.Arrays;
+import java.util.ArrayList;
+import java.util.Collections;
 import java.util.List;
-import java.util.stream.Collectors;
 import org.apache.hc.core5.http.ClassicHttpRequest;
 import org.apache.hc.core5.http.Header;
 import org.apache.hc.core5.http.HttpResponse;
@@ -77,9 +77,7 @@ protected String userAgent(ClassicHttpRequest request) {
 
   @Override
   protected List<String> requestHeader(ClassicHttpRequest request, String name) {
-    return Arrays.stream(request.getHeaders(name))
-        .map(Header::getValue)
-        .collect(Collectors.toList());
+    return headersToList(request.getHeaders(name));
   }
 
   @Override
@@ -142,8 +140,18 @@ protected Long responseContentLengthUncompressed(
   @Override
   protected List<String> responseHeader(
       ClassicHttpRequest request, HttpResponse response, String name) {
-    return Arrays.stream(response.getHeaders(name))
-        .map(Header::getValue)
-        .collect(Collectors.toList());
+    return headersToList(response.getHeaders(name));
+  }
+
+  // minimize memory overhead by not using streams
+  private static List<String> headersToList(Header[] headers) {
+    if (headers.length == 0) {
+      return Collections.emptyList();
+    }
+    List<String> headersList = new ArrayList<>(headers.length);
+    for (int i = 0; i < headers.length; ++i) {
+      headersList.set(i, headers[i].getValue());
+    }
+    return headersList;
   }
 }
diff --git a/...emetry/javaagent/instrumentation/jaxrsclient/v1_1/JaxRsClientHttpAttributesExtractor.java b/...emetry/javaagent/instrumentation/jaxrsclient/v1_1/JaxRsClientHttpAttributesExtractor.java
@@ -12,8 +12,8 @@
 import io.opentelemetry.instrumentation.api.instrumenter.http.HttpClientAttributesExtractor;
 import io.opentelemetry.javaagent.instrumentation.api.config.HttpHeadersConfig;
 import io.opentelemetry.semconv.trace.attributes.SemanticAttributes;
+import java.util.ArrayList;
 import java.util.List;
-import java.util.stream.Collectors;
 import org.checkerframework.checker.nullness.qual.Nullable;
 
 final class JaxRsClientHttpAttributesExtractor
@@ -41,9 +41,16 @@ protected String url(ClientRequest httpRequest) {
 
   @Override
   protected List<String> requestHeader(ClientRequest httpRequest, String name) {
-    return httpRequest.getHeaders().getOrDefault(name, emptyList()).stream()
-        .map(String::valueOf)
-        .collect(Collectors.toList());
+    List<Object> rawHeaders = httpRequest.getHeaders().getOrDefault(name, emptyList());
+    if (rawHeaders.isEmpty()) {
+      return emptyList();
+    }
+    List<String> stringHeaders = new ArrayList<>(rawHeaders.size());
+    int i = 0;
+    for (Object headerValue : rawHeaders) {
+      stringHeaders.set(i++, String.valueOf(headerValue));
+    }
+    return stringHeaders;
   }
 
   @Override

diff --git a/...try/javaagent/instrumentation/jaxrsclient/v2_0/ResteasyClientHttpAttributesExtractor.java b/...try/javaagent/instrumentation/jaxrsclient/v2_0/ResteasyClientHttpAttributesExtractor.java
@@ -10,8 +10,8 @@
 import io.opentelemetry.instrumentation.api.instrumenter.http.HttpClientAttributesExtractor;
 import io.opentelemetry.javaagent.instrumentation.api.config.HttpHeadersConfig;
 import io.opentelemetry.semconv.trace.attributes.SemanticAttributes;
+import java.util.ArrayList;
 import java.util.List;
-import java.util.stream.Collectors;
 import javax.ws.rs.core.Response;
 import org.checkerframework.checker.nullness.qual.Nullable;
 import org.jboss.resteasy.client.jaxrs.internal.ClientInvocation;
@@ -40,9 +40,16 @@ protected String url(ClientInvocation httpRequest) {
 
   @Override
   protected List<String> requestHeader(ClientInvocation httpRequest, String name) {
-    return httpRequest.getHeaders().getHeaders().getOrDefault(name, emptyList()).stream()
-        .map(String::valueOf)
-        .collect(Collectors.toList());
+    List<Object> rawHeaders = httpRequest.getHeaders().getHeaders().getOrDefault(name, emptyList());
+    if (rawHeaders.isEmpty()) {
+      return emptyList();
+    }
+    List<String> stringHeaders = new ArrayList<>(rawHeaders.size());
+    int i = 0;
+    for (Object headerValue : rawHeaders) {
+      stringHeaders.set(i++, String.valueOf(headerValue));
+    }
+    return stringHeaders;
   }
 
   @Override

diff --git a/...in/java/io/opentelemetry/instrumentation/restlet/v1_0/RestletHttpAttributesExtractor.java b/...in/java/io/opentelemetry/instrumentation/restlet/v1_0/RestletHttpAttributesExtractor.java
@@ -10,13 +10,15 @@
 import io.opentelemetry.instrumentation.api.instrumenter.http.CapturedHttpHeaders;
 import io.opentelemetry.instrumentation.api.instrumenter.http.HttpServerAttributesExtractor;
 import io.opentelemetry.semconv.trace.attributes.SemanticAttributes;
+import java.util.ArrayList;
+import java.util.Collections;
 import java.util.List;
-import java.util.stream.Collectors;
 import org.checkerframework.checker.nullness.qual.Nullable;
 import org.restlet.data.Parameter;
 import org.restlet.data.Reference;
 import org.restlet.data.Request;
 import org.restlet.data.Response;
+import org.restlet.util.Series;
 
 final class RestletHttpAttributesExtractor
     extends HttpServerAttributesExtractor<Request, Response> {
@@ -61,9 +63,7 @@ protected String host(Request request) {
 
   @Override
   protected List<String> requestHeader(Request request, String name) {
-    return getHeaders(request).subList(name, /* ignoreCase = */ true).stream()
-        .map(Parameter::getValue)
-        .collect(Collectors.toList());
+    return parametersToList(getHeaders(request).subList(name, /* ignoreCase = */ true));
   }
 
   @Override
@@ -115,8 +115,19 @@ protected Integer statusCode(Request request, Response response) {
 
   @Override
   protected List<String> responseHeader(Request request, Response response, String name) {
-    return getHeaders(response).subList(name, /* ignoreCase = */ true).stream()
-        .map(Parameter::getValue)
-        .collect(Collectors.toList());
+    return parametersToList(getHeaders(response).subList(name, /* ignoreCase = */ true));
+  }
+
+  // minimize memory overhead by not using streams
+  private static List<String> parametersToList(Series<Parameter> headers) {
+    if (headers.isEmpty()) {
+      return Collections.emptyList();
+    }
+    List<String> stringHeaders = new ArrayList<>(headers.size());
+    int i = 0;
+    for (Parameter header : headers) {
+      stringHeaders.set(i++, header.getValue());
+    }
+    return stringHeaders;
   }
 }