add checkstyle

Signed-off-by: Gregor Zeitlinger <[email protected]>

Author: zeitlinger

checkstyle.xml

@@ -14,12 +14,6 @@ public interface StateSetDataPoint extends DataPoint {
    */
   void setTrue(String state);
 
-  /**
-   * {@code state} must be one of the states from when the {@code StateSet} was created with {@link
-   * io.prometheus.metrics.core.metrics.StateSet.Builder#states(String...)}.
-   */
-  void setFalse(String state);
-
   /**
    * {@code state} must be one of the states from when the {@code StateSet} was created with {@link
    * io.prometheus.metrics.core.metrics.StateSet.Builder#states(Class)}.
@@ -28,6 +22,12 @@ default void setTrue(Enum<?> state) {
     setTrue(state.toString());
   }
 
+  /**
+   * {@code state} must be one of the states from when the {@code StateSet} was created with {@link
+   * io.prometheus.metrics.core.metrics.StateSet.Builder#states(String...)}.
+   */
+  void setFalse(String state);
+
   /**
    * {@code state} must be one of the states from when the {@code StateSet} was created with {@link
    * io.prometheus.metrics.core.metrics.StateSet.Builder#states(Class)}.

prometheus-metrics-core/src/main/java/io/prometheus/metrics/core/datapoints/StateSetDataPoint.java

@@ -26,7 +26,7 @@
 import java.util.LinkedList;
 import java.util.ListIterator;
 
-//CHECKSTYLE:OFF: checkstyle
+// CHECKSTYLE:OFF: checkstyle
 
 /**
  * Algorithm solving the "Targeted Quantile Problem" as described in "Effective Computation of
@@ -276,4 +276,4 @@ public String toString() {
   }
 }
 
-//CHECKSTYLE:ON: checkstyle
+// CHECKSTYLE:ON: checkstyle

prometheus-metrics-core/src/main/java/io/prometheus/metrics/core/metrics/CKMSQuantiles.java

@@ -63,7 +63,7 @@ public class Histogram extends StatefulMetric<DistributionDataPoint, Histogram.D
     implements DistributionDataPoint {
 
   // nativeSchema == CLASSIC_HISTOGRAM indicates that this is a classic histogram only.
-  private final int CLASSIC_HISTOGRAM = Integer.MIN_VALUE;
+  private static final int CLASSIC_HISTOGRAM = Integer.MIN_VALUE;
 
   // NATIVE_BOUNDS is used to look up the native bucket index depending on the current schema.
   private static final double[][] NATIVE_BOUNDS;
@@ -152,7 +152,7 @@ private Histogram(Histogram.Builder builder, PrometheusProperties prometheusProp
     double min =
         getConfigProperty(properties, MetricsProperties::getHistogramNativeMinZeroThreshold);
     nativeMaxZeroThreshold =
-        max == builder.DEFAULT_NATIVE_MAX_ZERO_THRESHOLD && min > max ? min : max;
+        max == Builder.DEFAULT_NATIVE_MAX_ZERO_THRESHOLD && min > max ? min : max;
     nativeMinZeroThreshold = Math.min(min, nativeMaxZeroThreshold);
     nativeMaxBuckets =
         getConfigProperty(properties, MetricsProperties::getHistogramNativeMaxNumberOfBuckets);
@@ -447,9 +447,9 @@ private void maybeScaleDown(AtomicBoolean wasReset) {
             // Now we are in the synchronized block while new observations go into the buffer.
             // Check again if we need to limit the bucket size, because another thread might
             // have limited it in the meantime.
-            int nBuckets =
+            int numBuckets =
                 nativeBucketsForPositiveValues.size() + nativeBucketsForNegativeValues.size();
-            if (nBuckets <= nativeMaxBuckets || nativeSchema == -4) {
+            if (numBuckets <= nativeMaxBuckets || nativeSchema == -4) {
               return null;
             }
             if (maybeReset()) {
@@ -668,11 +668,11 @@ public static class Builder extends StatefulMetric.Builder<Histogram.Builder, Hi
     public static final double[] DEFAULT_CLASSIC_UPPER_BOUNDS =
         new double[] {.005, .01, .025, .05, .1, .25, .5, 1, 2.5, 5, 10};
 
-    private final double DEFAULT_NATIVE_MIN_ZERO_THRESHOLD = Math.pow(2.0, -128);
-    private final double DEFAULT_NATIVE_MAX_ZERO_THRESHOLD = Math.pow(2.0, -128);
-    private final int DEFAULT_NATIVE_INITIAL_SCHEMA = 5;
-    private final int DEFAULT_NATIVE_MAX_NUMBER_OF_BUCKETS = 160;
-    private final long DEFAULT_NATIVE_RESET_DURATION_SECONDS = 0; // 0 means no reset
+    private static final double DEFAULT_NATIVE_MIN_ZERO_THRESHOLD = Math.pow(2.0, -128);
+    private static final double DEFAULT_NATIVE_MAX_ZERO_THRESHOLD = Math.pow(2.0, -128);
+    private static final int DEFAULT_NATIVE_INITIAL_SCHEMA = 5;
+    private static final int DEFAULT_NATIVE_MAX_NUMBER_OF_BUCKETS = 160;
+    private static final long DEFAULT_NATIVE_RESET_DURATION_SECONDS = 0; // 0 means no reset
 
     private Boolean nativeOnly;
     private Boolean classicOnly;

prometheus-metrics-core/src/main/java/io/prometheus/metrics/core/metrics/Histogram.java

@@ -76,16 +76,6 @@ public StateSetSnapshot collect() {
     return (StateSetSnapshot) super.collect();
   }
 
-  @Override
-  public void setTrue(String state) {
-    getNoLabels().setTrue(state);
-  }
-
-  @Override
-  public void setFalse(String state) {
-    getNoLabels().setFalse(state);
-  }
-
   @Override
   protected StateSetSnapshot collect(List<Labels> labels, List<DataPoint> metricDataList) {
     List<StateSetSnapshot.StateSetDataPointSnapshot> data = new ArrayList<>(labels.size());
@@ -97,6 +87,16 @@ protected StateSetSnapshot collect(List<Labels> labels, List<DataPoint> metricDa
     return new StateSetSnapshot(getMetadata(), data);
   }
 
+  @Override
+  public void setTrue(String state) {
+    getNoLabels().setTrue(state);
+  }
+
+  @Override
+  public void setFalse(String state) {
+    getNoLabels().setFalse(state);
+  }
+
   @Override
   protected DataPoint newDataPoint() {
     return new DataPoint();

prometheus-metrics-core/src/main/java/io/prometheus/metrics/core/metrics/StateSet.java

@@ -46,7 +46,6 @@ public PrometheusScrapeHandler(PrometheusProperties config, PrometheusRegistry r
   public void handleRequest(PrometheusHttpExchange exchange) throws IOException {
     try {
       PrometheusHttpRequest request = exchange.getRequest();
-      PrometheusHttpResponse response = exchange.getResponse();
       MetricSnapshots snapshots = scrape(request);
       if (writeDebugResponse(snapshots, exchange)) {
         return;
@@ -57,6 +56,7 @@ public void handleRequest(PrometheusHttpExchange exchange) throws IOException {
       ExpositionFormatWriter writer = expositionFormats.findWriter(acceptHeader);
       writer.write(responseBuffer, snapshots);
       lastResponseSize.set(responseBuffer.size());
+      PrometheusHttpResponse response = exchange.getResponse();
       response.setHeader("Content-Type", writer.getContentType());
 
       if (shouldUseCompression(request)) {
@@ -106,16 +106,6 @@ private Predicate<String> makeNameFilter(ExporterFilterProperties props) {
     }
   }
 
-  private MetricSnapshots scrape(PrometheusHttpRequest request) {
-
-    Predicate<String> filter = makeNameFilter(request.getParameterValues("name[]"));
-    if (filter != null) {
-      return registry.scrape(filter, request);
-    } else {
-      return registry.scrape(request);
-    }
-  }
-
   private Predicate<String> makeNameFilter(String[] includedNames) {
     Predicate<String> result = null;
     if (includedNames != null && includedNames.length > 0) {
@@ -129,6 +119,16 @@ private Predicate<String> makeNameFilter(String[] includedNames) {
     return result;
   }
 
+  private MetricSnapshots scrape(PrometheusHttpRequest request) {
+
+    Predicate<String> filter = makeNameFilter(request.getParameterValues("name[]"));
+    if (filter != null) {
+      return registry.scrape(filter, request);
+    } else {
+      return registry.scrape(request);
+    }
+  }
+
   private boolean writeDebugResponse(MetricSnapshots snapshots, PrometheusHttpExchange exchange)
       throws IOException {
     String debugParam = exchange.getRequest().getParameter("debug");

prometheus-metrics-exporter-common/src/main/java/io/prometheus/metrics/exporter/common/PrometheusScrapeHandler.java

@@ -44,7 +44,7 @@ public Collection<MetricData> collectAllMetrics() {
     // registry.scrape(filter) if a filter is configured, like in the Servlet exporter.
     MetricSnapshots snapshots = registry.scrape();
     Resource resourceWithTargetInfo = resource.merge(resourceFromTargetInfo(snapshots));
-    InstrumentationScopeInfo scopeFromInfo = instrumentationScopeFromOTelScopeInfo(snapshots);
+    InstrumentationScopeInfo scopeFromInfo = instrumentationScopeFromOtelScopeInfo(snapshots);
     List<MetricData> result = new ArrayList<>(snapshots.size());
     MetricDataFactory factory =
         new MetricDataFactory(
@@ -93,7 +93,7 @@ private Resource resourceFromTargetInfo(MetricSnapshots snapshots) {
     return result.build();
   }
 
-  private InstrumentationScopeInfo instrumentationScopeFromOTelScopeInfo(
+  private InstrumentationScopeInfo instrumentationScopeFromOtelScopeInfo(
       MetricSnapshots snapshots) {
     for (MetricSnapshot snapshot : snapshots) {
       if (snapshot.getMetadata().getPrometheusName().equals("otel_scope")

prometheus-metrics-exporter-opentelemetry/src/main/java/io/prometheus/metrics/exporter/opentelemetry/PrometheusMetricProducer.java

@@ -10,10 +10,24 @@
 import io.prometheus.metrics.model.registry.Collector;
 import io.prometheus.metrics.model.registry.MultiCollector;
 import io.prometheus.metrics.model.registry.PrometheusRegistry;
-import java.io.*;
-import java.net.*;
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.io.UnsupportedEncodingException;
+import java.net.HttpURLConnection;
+import java.net.InetAddress;
+import java.net.MalformedURLException;
+import java.net.URI;
+import java.net.URL;
+import java.net.URLEncoder;
+import java.net.UnknownHostException;
 import java.nio.charset.StandardCharsets;
-import java.util.*;
+import java.util.Base64;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.TreeMap;
 
 /**
  * Export metrics via the <a href="https://github.com/prometheus/pushgateway">Prometheus