add branch coverage, better javadoc lints

checkstyle-suppressions.xml

@@ -5,5 +5,20 @@
   "https://checkstyle.org/dtds/suppressions_1_2.dtd">
 
 <suppressions>
-    <suppress checks="Javadoc" files="."/>
+  <!-- Suppress Javadoc paragraph formatting (empty line before <p> tag) globally. This is a
+       stylistic check that would require fixing hundreds of locations. We still enforce that
+       public APIs have documentation via other Javadoc checks. -->
+  <suppress checks="JavadocParagraph" files="."/>
+
+  <!-- Suppress all Javadoc checks for internal implementation packages -->
+  <suppress checks="Javadoc" files=".*[/\\]internal[/\\].*"/>
+
+  <!-- Suppress all Javadoc checks for example code -->
+  <suppress checks="Javadoc" files=".*[/\\]examples[/\\].*"/>
+
+  <!-- Suppress all Javadoc checks for benchmark code -->
+  <suppress checks="Javadoc" files=".*[/\\]benchmarks[/\\].*"/>
+
+  <!-- Suppress all Javadoc checks for integration tests -->
+  <suppress checks="Javadoc" files=".*[/\\]integration-tests[/\\].*"/>
 </suppressions>

pom.xml

@@ -234,6 +234,8 @@
           <excludes>
             <exclude>**/generated/**</exclude>
             <exclude>**/*BlockingRejectedExecutionHandler*</exclude>
+            <exclude>**/*AllocationCountingNotificationListener*</exclude>
+            <exclude>**/*MapperConfig*</exclude>
           </excludes>
         </configuration>
         <executions>
@@ -264,6 +266,11 @@
                       <value>COVEREDRATIO</value>
                       <minimum>${jacoco.line-coverage}</minimum>
                     </limit>
+                    <limit>
+                      <counter>BRANCH</counter>
+                      <value>COVEREDRATIO</value>
+                      <minimum>0.50</minimum>
+                    </limit>
                   </limits>
                 </rule>
               </rules>

prometheus-metrics-config/src/test/java/io/prometheus/metrics/config/ExporterOpenTelemetryPropertiesTest.java

@@ -1,6 +1,7 @@
 package io.prometheus.metrics.config;
 
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
 
 import java.util.HashMap;
 import java.util.Map;
@@ -68,4 +69,40 @@ void builder() {
             .build();
     assertValues(properties);
   }
+
+  @Test
+  void builderWithHttpProtobuf() {
+    ExporterOpenTelemetryProperties properties =
+        ExporterOpenTelemetryProperties.builder().protocol("http/protobuf").build();
+    assertThat(properties.getProtocol()).isEqualTo("http/protobuf");
+  }
+
+  @Test
+  void builderWithInvalidProtocol() {
+    assertThatExceptionOfType(IllegalArgumentException.class)
+        .isThrownBy(() -> ExporterOpenTelemetryProperties.builder().protocol("invalid"))
+        .withMessage("invalid: Unsupported protocol. Expecting grpc or http/protobuf");
+  }
+
+  @Test
+  void builderWithInvalidIntervalSeconds() {
+    assertThatExceptionOfType(IllegalArgumentException.class)
+        .isThrownBy(() -> ExporterOpenTelemetryProperties.builder().intervalSeconds(0))
+        .withMessage("0: Expecting intervalSeconds > 0");
+
+    assertThatExceptionOfType(IllegalArgumentException.class)
+        .isThrownBy(() -> ExporterOpenTelemetryProperties.builder().intervalSeconds(-1))
+        .withMessage("-1: Expecting intervalSeconds > 0");
+  }
+
+  @Test
+  void builderWithInvalidTimeoutSeconds() {
+    assertThatExceptionOfType(IllegalArgumentException.class)
+        .isThrownBy(() -> ExporterOpenTelemetryProperties.builder().timeoutSeconds(0))
+        .withMessage("0: Expecting timeoutSeconds > 0");
+
+    assertThatExceptionOfType(IllegalArgumentException.class)
+        .isThrownBy(() -> ExporterOpenTelemetryProperties.builder().timeoutSeconds(-1))
+        .withMessage("-1: Expecting timeoutSeconds > 0");
+  }
 }

prometheus-metrics-config/src/test/java/io/prometheus/metrics/config/ExporterPropertiesTest.java

@@ -56,5 +56,35 @@ void builder() {
             .build();
     assertThat(properties.getIncludeCreatedTimestamps()).isTrue();
     assertThat(properties.getExemplarsOnAllMetricTypes()).isTrue();
+    assertThat(properties.getPrometheusTimestampsInMs()).isFalse();
+  }
+
+  @Test
+  void defaultValues() {
+    ExporterProperties properties = ExporterProperties.builder().build();
+    assertThat(properties.getIncludeCreatedTimestamps()).isFalse();
+    assertThat(properties.getExemplarsOnAllMetricTypes()).isFalse();
+    assertThat(properties.getPrometheusTimestampsInMs()).isFalse();
+  }
+
+  @Test
+  void prometheusTimestampsInMs() {
+    ExporterProperties properties =
+        ExporterProperties.builder().prometheusTimestampsInMs(true).build();
+    assertThat(properties.getPrometheusTimestampsInMs()).isTrue();
+
+    properties =
+        load(new HashMap<>(Map.of("io.prometheus.exporter.prometheus_timestamps_in_ms", "true")));
+    assertThat(properties.getPrometheusTimestampsInMs()).isTrue();
+
+    assertThatExceptionOfType(PrometheusPropertiesException.class)
+        .isThrownBy(
+            () ->
+                load(
+                    new HashMap<>(
+                        Map.of("io.prometheus.exporter.prometheus_timestamps_in_ms", "invalid"))))
+        .withMessage(
+            "io.prometheus.exporter.prometheus_timestamps_in_ms: Expecting 'true' or 'false'. Found:"
+                + " invalid");
   }
 }

prometheus-metrics-config/src/test/java/io/prometheus/metrics/config/ExporterPushgatewayPropertiesTest.java

@@ -30,6 +30,50 @@ void load() {
                 + " Found: foo");
   }
 
+  @Test
+  void loadWithHttps() {
+    ExporterPushgatewayProperties properties =
+        load(Map.of("io.prometheus.exporter.pushgateway.scheme", "https"));
+    assertThat(properties.getScheme()).isEqualTo("https");
+  }
+
+  @Test
+  void loadWithEscapingSchemes() {
+    ExporterPushgatewayProperties properties =
+        load(Map.of("io.prometheus.exporter.pushgateway.escaping_scheme", "allow-utf-8"));
+    assertThat(properties.getEscapingScheme()).isEqualTo(EscapingScheme.ALLOW_UTF8);
+
+    properties = load(Map.of("io.prometheus.exporter.pushgateway.escaping_scheme", "values"));
+    assertThat(properties.getEscapingScheme()).isEqualTo(EscapingScheme.VALUE_ENCODING_ESCAPING);
+
+    properties = load(Map.of("io.prometheus.exporter.pushgateway.escaping_scheme", "underscores"));
+    assertThat(properties.getEscapingScheme()).isEqualTo(EscapingScheme.UNDERSCORE_ESCAPING);
+
+    properties = load(Map.of("io.prometheus.exporter.pushgateway.escaping_scheme", "dots"));
+    assertThat(properties.getEscapingScheme()).isEqualTo(EscapingScheme.DOTS_ESCAPING);
+  }
+
+  @Test
+  void loadWithInvalidEscapingScheme() {
+    assertThatExceptionOfType(PrometheusPropertiesException.class)
+        .isThrownBy(
+            () -> load(Map.of("io.prometheus.exporter.pushgateway.escaping_scheme", "invalid")))
+        .withMessage(
+            "io.prometheus.exporter.pushgateway.escaping_scheme: Illegal value. Expecting"
+                + " 'allow-utf-8', 'values', 'underscores', or 'dots'. Found: invalid");
+  }
+
+  @Test
+  void loadWithTimeouts() {
+    ExporterPushgatewayProperties properties =
+        load(
+            Map.of(
+                "io.prometheus.exporter.pushgateway.connect_timeout_seconds", "5",
+                "io.prometheus.exporter.pushgateway.read_timeout_seconds", "10"));
+    assertThat(properties.getConnectTimeout()).isEqualTo(Duration.ofSeconds(5));
+    assertThat(properties.getReadTimeout()).isEqualTo(Duration.ofSeconds(10));
+  }
+
   private static ExporterPushgatewayProperties load(Map<String, String> map) {
     Map<Object, Object> regularProperties = new HashMap<>(map);
     PropertySource propertySource = new PropertySource(regularProperties);

prometheus-metrics-config/src/test/java/io/prometheus/metrics/config/PrometheusPropertiesTest.java

@@ -70,4 +70,62 @@ void testBuilder() {
     assertThat(result.getMetricProperties("unknown_metric")).isNull();
     assertThat(result.getExporterProperties()).isSameAs(defaults.getExporterProperties());
   }
+
+  @Test
+  void testMetricNameNormalization() {
+    PrometheusProperties.Builder builder = PrometheusProperties.builder();
+    MetricsProperties customProps =
+        MetricsProperties.builder().histogramClassicUpperBounds(0.1, 0.5).build();
+
+    // Test that metric names with dots are normalized to underscores
+    builder.putMetricProperty("my.metric.name", customProps);
+    PrometheusProperties result = builder.build();
+
+    // Should be able to retrieve with dots
+    assertThat(result.getMetricProperties("my.metric.name")).isSameAs(customProps);
+    // Should also be able to retrieve with underscores
+    assertThat(result.getMetricProperties("my_metric_name")).isSameAs(customProps);
+  }
+
+  @Test
+  void testMetricNameWithInvalidCharacters() {
+    PrometheusProperties.Builder builder = PrometheusProperties.builder();
+    MetricsProperties customProps =
+        MetricsProperties.builder().histogramClassicUpperBounds(0.1, 0.5).build();
+
+    // Test that invalid characters are converted to underscores
+    builder.putMetricProperty("metric-name@with#invalid$chars", customProps);
+    PrometheusProperties result = builder.build();
+
+    // Should normalize invalid characters to underscores
+    assertThat(result.getMetricProperties("metric-name@with#invalid$chars")).isSameAs(customProps);
+    assertThat(result.getMetricProperties("metric_name_with_invalid_chars")).isSameAs(customProps);
+  }
+
+  @Test
+  void testMetricNameWithValidCharacters() {
+    PrometheusProperties.Builder builder = PrometheusProperties.builder();
+    MetricsProperties customProps =
+        MetricsProperties.builder().histogramClassicUpperBounds(0.1, 0.5).build();
+
+    // Test valid characters: letters, numbers (not at start), underscore, colon
+    builder.putMetricProperty("my_metric:name123", customProps);
+    PrometheusProperties result = builder.build();
+
+    assertThat(result.getMetricProperties("my_metric:name123")).isSameAs(customProps);
+  }
+
+  @Test
+  void testMetricNameStartingWithNumber() {
+    PrometheusProperties.Builder builder = PrometheusProperties.builder();
+    MetricsProperties customProps =
+        MetricsProperties.builder().histogramClassicUpperBounds(0.1, 0.5).build();
+
+    // First digit is invalid (i=0), but subsequent digits are valid (i>0)
+    builder.putMetricProperty("123metric", customProps);
+    PrometheusProperties result = builder.build();
+
+    assertThat(result.getMetricProperties("123metric")).isSameAs(customProps);
+    assertThat(result.getMetricProperties("_23metric")).isSameAs(customProps);
+  }
 }

prometheus-metrics-exporter-httpserver/pom.xml

@@ -19,7 +19,7 @@
 
   <properties>
     <automatic.module.name>io.prometheus.metrics.exporter.httpserver</automatic.module.name>
-    <jacoco.line-coverage>0.45</jacoco.line-coverage>
+    <jacoco.line-coverage>0.60</jacoco.line-coverage>
   </properties>
 
   <dependencies>

prometheus-metrics-exporter-httpserver/src/test/java/io/prometheus/metrics/exporter/httpserver/HTTPServerTest.java

@@ -85,6 +85,29 @@ public Result authenticate(HttpExchange exchange) {
     run(server, "/", 204, "");
   }
 
+  @Test
+  void testSubjectDoAsWithInvalidSubject() throws Exception {
+    Authenticator authenticator =
+        new Authenticator() {
+          @Override
+          public Result authenticate(HttpExchange exchange) {
+            exchange.setAttribute("aa", "not-a-subject");
+            return new Success(new HttpPrincipal("user", "/"));
+          }
+        };
+
+    HttpHandler handler = exchange -> exchange.sendResponseHeaders(204, -1);
+    HTTPServer server =
+        HTTPServer.builder()
+            .port(0)
+            .authenticator(authenticator)
+            .defaultHandler(handler)
+            .authenticatedSubjectAttributeName("aa")
+            .buildAndStart();
+
+    run(server, "/", 403, "");
+  }
+
   @Test
   void defaultHandler() throws Exception {
     run(

prometheus-metrics-exporter-httpserver/src/test/java/io/prometheus/metrics/exporter/httpserver/HttpExchangeAdapterTest.java

@@ -0,0 +1,49 @@
+package io.prometheus.metrics.exporter.httpserver;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+
+import com.sun.net.httpserver.Headers;
+import com.sun.net.httpserver.HttpExchange;
+import java.net.URI;
+import java.util.List;
+import org.junit.jupiter.api.Test;
+
+class HttpExchangeAdapterTest {
+
+  @Test
+  void getRequestPath() {
+    HttpExchange httpExchange = mock(HttpExchange.class);
+    when(httpExchange.getRequestURI()).thenReturn(URI.create("/metrics?name=test"));
+    HttpExchangeAdapter adapter = new HttpExchangeAdapter(httpExchange);
+    assertThat(adapter.getRequest().getRequestPath()).isEqualTo("/metrics");
+  }
+
+  @Test
+  void getRequestPathWithoutQueryString() {
+    HttpExchange httpExchange = mock(HttpExchange.class);
+    when(httpExchange.getRequestURI()).thenReturn(URI.create("/metrics"));
+    HttpExchangeAdapter adapter = new HttpExchangeAdapter(httpExchange);
+    assertThat(adapter.getRequest().getRequestPath()).isEqualTo("/metrics");
+  }
+
+  @Test
+  void getHeadersWhenPresent() {
+    HttpExchange httpExchange = mock(HttpExchange.class);
+    Headers headers = new Headers();
+    headers.put("Accept", List.of("text/plain"));
+    when(httpExchange.getRequestHeaders()).thenReturn(headers);
+    HttpExchangeAdapter adapter = new HttpExchangeAdapter(httpExchange);
+    assertThat(adapter.getRequest().getHeaders("Accept").nextElement()).isEqualTo("text/plain");
+  }
+
+  @Test
+  void getHeadersWhenNotPresent() {
+    HttpExchange httpExchange = mock(HttpExchange.class);
+    Headers headers = new Headers();
+    when(httpExchange.getRequestHeaders()).thenReturn(headers);
+    HttpExchangeAdapter adapter = new HttpExchangeAdapter(httpExchange);
+    assertThat(adapter.getRequest().getHeaders("Accept").hasMoreElements()).isFalse();
+  }
+}