SOLR-13733: add class-level javadocs for 4 org.apache.solr.metrics classes

solr/core/src/java/org/apache/solr/metrics/FilteringSolrMetricReporter.java

@@ -21,6 +21,9 @@ import java.util.List;
 
 import com.codahale.metrics.MetricFilter;
 
+/**
+ * A {@link SolrMetricReporter} that supports (prefix) filters.
+ */
 public abstract class FilteringSolrMetricReporter extends SolrMetricReporter {
 
   protected List<String> filters = new ArrayList<>();

solr/core/src/java/org/apache/solr/metrics/SolrMetricManager.java

@@ -293,6 +293,10 @@ public class SolrMetricManager {
     }
   }
 
+  /**
+   * An implementation of {@link MetricFilter} that selects metrics
+   * that match any filter in a list of filters.
+   */
   public static class OrFilter implements MetricFilter {
     List<MetricFilter> filters = new ArrayList<>();
 
@@ -323,6 +327,10 @@ public class SolrMetricManager {
     }
   }
 
+  /**
+   * An implementation of {@link MetricFilter} that selects metrics
+   * that match all filters in a list of filters.
+   */
   public static class AndFilter implements MetricFilter {
     List<MetricFilter> filters = new ArrayList<>();
 

solr/core/src/java/org/apache/solr/metrics/reporters/jmx/JmxMetricsReporter.java

@@ -73,6 +73,9 @@ public class JmxMetricsReporter implements Reporter, Closeable {
     return new Builder(registry);
   }
 
+  /**
+   * Builder for the {@link JmxMetricsReporter} class.
+   */
   public static class Builder {
     private final MetricRegistry registry;
     private MBeanServer mBeanServer;

solr/core/src/java/org/apache/solr/metrics/reporters/solr/SolrReporter.java

@@ -116,6 +116,9 @@ public class SolrReporter extends ScheduledReporter {
     }
   }
 
+  /**
+   * Builder for the {@link SolrReporter} class.
+   */
   public static class Builder {
     private final SolrMetricManager metricManager;
     private final List<Report> reports;