Separated memoization from signature matching

pmd · Aug 4, 2017 · 152dddf · 152dddf
1 parent 909f989
commit 152dddf
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Showing 22 changed files with 271 additions and 170 deletions.
diff --git a/pmd-core/src/main/java/net/sourceforge/pmd/lang/metrics/AbstractMetricsComputer.java b/pmd-core/src/main/java/net/sourceforge/pmd/lang/metrics/AbstractMetricsComputer.java
@@ -63,7 +63,7 @@ public double computeWithResultOption(MetricKey<O> key, T node, boolean force, M
         List<Double> values = new ArrayList<>();
         for (O op : ops) {
             if (key.supports(op)) {
-                MetricMemoizer<O> opStats = stats.getOperationStats(op.getQualifiedName());
+                MetricMemoizer<O> opStats = stats.getOperationMemoizer(op.getQualifiedName());
                 double val = this.computeForOperation(key, op, force, version, opStats);
                 if (val != Double.NaN) {
                     values.add(val);

diff --git a/pmd-core/src/main/java/net/sourceforge/pmd/lang/metrics/AbstractMetricsFacade.java b/pmd-core/src/main/java/net/sourceforge/pmd/lang/metrics/AbstractMetricsFacade.java
@@ -30,9 +30,9 @@ public abstract class AbstractMetricsFacade<T extends QualifiableNode, O extends
 
 
     /**
-     * Gets the language-specific project mirror.
+     * Gets the language-specific project memoizer.
      *
-     * @return The project mirror
+     * @return The project memoizer
      */
     protected abstract ProjectMemoizer<T, O> getLanguageSpecificProjectMemoizer();
 
@@ -56,7 +56,7 @@ public double computeForType(MetricKey<T> key, T node, MetricVersion version) {
         }
 
         MetricVersion safeVersion = (version == null) ? Version.STANDARD : version;
-        MetricMemoizer<T> memoizer = getLanguageSpecificProjectMemoizer().getClassStats(node.getQualifiedName());
+        MetricMemoizer<T> memoizer = getLanguageSpecificProjectMemoizer().getClassMemoizer(node.getQualifiedName());
 
         return memoizer == null ? Double.NaN
                                 : getLanguageSpecificComputer().computeForType(key, node, false, safeVersion, memoizer);
@@ -82,7 +82,7 @@ public double computeForOperation(MetricKey<O> key, O node,
         }
 
         MetricVersion safeVersion = (version == null) ? Version.STANDARD : version;
-        MetricMemoizer<O> memoizer = getLanguageSpecificProjectMemoizer().getOperationStats(node.getQualifiedName());
+        MetricMemoizer<O> memoizer = getLanguageSpecificProjectMemoizer().getOperationMemoizer(node.getQualifiedName());
 
         return memoizer == null ? Double.NaN
                                 : getLanguageSpecificComputer().computeForOperation(key, node, false,

diff --git a/.../lang/metrics/AbstractMetricMemoizer.java → ...pmd/lang/metrics/BasicMetricMemoizer.java b/.../lang/metrics/AbstractMetricMemoizer.java → ...pmd/lang/metrics/BasicMetricMemoizer.java
@@ -10,13 +10,13 @@
 import net.sourceforge.pmd.lang.ast.Node;
 
 /**
- * Base class for metric memoizers.
+ * Basic implementation of a metric memoizer.
  *
  * @param <N> Type of node on which the memoized metric can be computed
  *
  * @author Clément Fournier
  */
-public abstract class AbstractMetricMemoizer<N extends Node> implements MetricMemoizer<N> {
+public class BasicMetricMemoizer<N extends Node> implements MetricMemoizer<N> {
 
 
     private final Map<ParameterizedMetricKey<N>, Double> memo = new HashMap<>();

diff --git a/pmd-core/src/main/java/net/sourceforge/pmd/lang/metrics/BasicProjectMemoizer.java b/pmd-core/src/main/java/net/sourceforge/pmd/lang/metrics/BasicProjectMemoizer.java
@@ -0,0 +1,50 @@
+/**
+ * BSD-style license; for more info see http://pmd.sourceforge.net/license.html
+ */
+
+package net.sourceforge.pmd.lang.metrics;
+
+import java.util.HashMap;
+import java.util.Map;
+
+import net.sourceforge.pmd.lang.ast.QualifiableNode;
+import net.sourceforge.pmd.lang.ast.QualifiedName;
+
+/**
+ * Simple implementation of a project memoizer. Memoizers are accessible in constant time, provided the QualifiedName's
+ * hashCode is well distributed.
+ *
+ * @param <T> Type of type declaration nodes of the language
+ * @param <O> Type of operation declaration nodes of the language
+ *
+ * @author Clément Fournier
+ */
+public class BasicProjectMemoizer<T extends QualifiableNode, O extends QualifiableNode> implements ProjectMemoizer<T, O> {
+
+    private Map<QualifiedName, MetricMemoizer<T>> classes = new HashMap<>();
+    private Map<QualifiedName, MetricMemoizer<O>> operations = new HashMap<>();
+
+
+    @Override
+    public void addClassMemoizer(QualifiedName qname) {
+        classes.put(qname, new BasicMetricMemoizer<T>());
+    }
+
+
+    @Override
+    public void addOperationMemoizer(QualifiedName qname) {
+        operations.put(qname, new BasicMetricMemoizer<O>());
+    }
+
+
+    @Override
+    public MetricMemoizer<O> getOperationMemoizer(QualifiedName qname) {
+        return operations.get(qname);
+    }
+
+
+    @Override
+    public MetricMemoizer<T> getClassMemoizer(QualifiedName qname) {
+        return classes.get(qname);
+    }
+}
diff --git a/pmd-core/src/main/java/net/sourceforge/pmd/lang/metrics/Metric.java b/pmd-core/src/main/java/net/sourceforge/pmd/lang/metrics/Metric.java
@@ -7,7 +7,8 @@
 import net.sourceforge.pmd.lang.ast.Node;
 
 /**
- * Umbrella marker interface for metrics.
+ * Object computing a metric on a node. Metric objects are be stateless, which means that instances of the same
+ * metric are all equal.
  *
  * @param <N> Type of nodes the metric can be computed on
  *

diff --git a/pmd-core/src/main/java/net/sourceforge/pmd/lang/metrics/MetricMemoizer.java b/pmd-core/src/main/java/net/sourceforge/pmd/lang/metrics/MetricMemoizer.java
@@ -7,7 +7,8 @@
 import net.sourceforge.pmd.lang.ast.Node;
 
 /**
- * Objects capable of memoizing metrics for a specific type of node, see eg ClassStats in the Java framework.
+ * Objects capable of memoizing metrics for a specific type of node. A default implementation is provided, see {@link
+ * BasicMetricMemoizer}.
  *
  * @param <N> Type of node on which the memoized metric can be computed
  *

diff --git a/pmd-core/src/main/java/net/sourceforge/pmd/lang/metrics/ProjectMemoizer.java b/pmd-core/src/main/java/net/sourceforge/pmd/lang/metrics/ProjectMemoizer.java
@@ -8,18 +8,8 @@
 import net.sourceforge.pmd.lang.ast.QualifiedName;
 
 /**
- * Object storing the memoizers of the analysed project, like PackageStats for Java. If retrieving eg an operation stats
- * is expensive, consider implementing a cache.
- *
- * <p>Language specific implementations should implement some signature matching utilities for metrics to use. The
- * details of how the mirror and its subcomponents are built must be kept out of the interfaces and visible only to the
- * language specific metric package. Metric implementations, even standard ones, should not have access to it.
- *
- * <p>While classes and operations are widespread and vary little in form across (class based at least) object-oriented
- * languages, the structure of a project is very language specific. For example, while an intuitive way to represent a
- * Java project is with a package tree, Apex has no package system. We consider here that there's no point providing
- * base implementations, so we use an interface. You could even implement it with a bunch of maps, which may yield good
- * results! // TODO:cf investigate that
+ * Object storing the memoizers of the analysed project. This object should ideally be kept separate from the
+ * SignatureMatcher if there is one. A base implementation is available, see {@link BasicProjectMemoizer}.
  *
  * @param <T> Type of type declaration nodes of the language
  * @param <O> Type of operation declaration nodes of the language
@@ -35,7 +25,7 @@ public interface ProjectMemoizer<T extends QualifiableNode, O extends Qualifiabl
      *
      * @return The correct memoizer, or null if it wasn't found
      */
-    MetricMemoizer<O> getOperationStats(QualifiedName qname);
+    MetricMemoizer<O> getOperationMemoizer(QualifiedName qname);
 
 
     /**
@@ -45,6 +35,23 @@ public interface ProjectMemoizer<T extends QualifiableNode, O extends Qualifiabl
      *
      * @return The correct memoizer, or null if it wasn't found
      */
-    MetricMemoizer<T> getClassStats(QualifiedName qname);
+    MetricMemoizer<T> getClassMemoizer(QualifiedName qname);
+
+
+    /**
+     * Adds a memoizer for the class identified by this qualified name.
+     *
+     * @param qname The qualified name of the class
+     */
+    void addClassMemoizer(QualifiedName qname);
+
+
+    /**
+     * Adds a memoizer for the operation identified by this qualified name.
+     *
+     * @param qname The qualified name of the operations
+     */
+    void addOperationMemoizer(QualifiedName qname);
+
 
 }
diff --git a/pmd-java/src/main/java/net/sourceforge/pmd/lang/java/ast/JavaQualifiedName.java b/pmd-java/src/main/java/net/sourceforge/pmd/lang/java/ast/JavaQualifiedName.java
@@ -11,7 +11,7 @@
 import net.sourceforge.pmd.lang.ast.QualifiedName;
 
 /**
- * Represents Qualified Names for use within the java project mirror.
+ * Represents Qualified Names for use within the java metrics framework.
  */
 public final class JavaQualifiedName implements QualifiedName {
 

diff --git a/pmd-java/src/main/java/net/sourceforge/pmd/lang/java/metrics/AbstractJavaMetric.java b/pmd-java/src/main/java/net/sourceforge/pmd/lang/java/metrics/AbstractJavaMetric.java
@@ -38,7 +38,17 @@ protected List<JavaQualifiedName> findAllCalls(ASTMethodOrConstructorDeclaration
      * @return A signature matcher
      */
     protected static JavaSignatureMatcher getSignatureMatcher() {
-        return JavaMetrics.getTopLevelPackageStats();
+        return JavaMetrics.getFacade().getTopLevelPackageStats();
+    }
+
+    @Override
+    public final boolean equals(Object o) {
+        return o != null && o.getClass() == this.getClass();
+    }
+
+    @Override
+    public final int hashCode() {
+        return getClass().hashCode();
     }
 
 }
diff --git a/pmd-java/src/main/java/net/sourceforge/pmd/lang/java/metrics/ClassStats.java b/pmd-java/src/main/java/net/sourceforge/pmd/lang/java/metrics/ClassStats.java
@@ -9,13 +9,11 @@
 import java.util.Map;
 import java.util.Set;
 
-import net.sourceforge.pmd.lang.java.ast.ASTAnyTypeDeclaration;
 import net.sourceforge.pmd.lang.java.ast.JavaQualifiedName;
 import net.sourceforge.pmd.lang.java.metrics.signature.JavaFieldSigMask;
 import net.sourceforge.pmd.lang.java.metrics.signature.JavaFieldSignature;
 import net.sourceforge.pmd.lang.java.metrics.signature.JavaOperationSigMask;
 import net.sourceforge.pmd.lang.java.metrics.signature.JavaOperationSignature;
-import net.sourceforge.pmd.lang.metrics.AbstractMetricMemoizer;
 
 /**
  * Statistics about a class, enum, interface, or annotation. Stores information about the contained members and their
@@ -28,7 +26,7 @@
  *
  * @author Clément Fournier
  */
-/* default */ class ClassStats extends AbstractMetricMemoizer<ASTAnyTypeDeclaration> {
+/* default */ class ClassStats {
 
     private Map<JavaOperationSignature, Map<String, OperationStats>> operations = new HashMap<>();
     private Map<JavaFieldSignature, Set<String>> fields = new HashMap<>();

diff --git a/pmd-java/src/main/java/net/sourceforge/pmd/lang/java/metrics/JavaMetrics.java b/pmd-java/src/main/java/net/sourceforge/pmd/lang/java/metrics/JavaMetrics.java
@@ -29,12 +29,12 @@ private JavaMetrics() { // Cannot be instantiated
 
 
     /**
-     * Returns the project mirror of the analysed project.
+     * Returns the underlying façade.
      *
-     * @return The project mirror
+     * @return The underlying façade instance
      */
-    static PackageStats getTopLevelPackageStats() {
-        return FACADE.getLanguageSpecificProjectMemoizer();
+    static JavaMetricsFacade getFacade() {
+        return FACADE;
     }
 
 

diff --git a/pmd-java/src/main/java/net/sourceforge/pmd/lang/java/metrics/JavaMetricsFacade.java b/pmd-java/src/main/java/net/sourceforge/pmd/lang/java/metrics/JavaMetricsFacade.java
@@ -17,6 +17,7 @@
 class JavaMetricsFacade extends AbstractMetricsFacade<ASTAnyTypeDeclaration, ASTMethodOrConstructorDeclaration> {
 
     private final PackageStats topLevelPackageStats = new PackageStats();
+    private final JavaProjectMemoizer memoizer = new JavaProjectMemoizer();
 
 
     /** Resets the entire data structure. Used for tests. */
@@ -25,12 +26,22 @@ void reset() {
     }
 
 
-    @Override
-    public PackageStats getLanguageSpecificProjectMemoizer() {
+    /**
+     * Gets the top level package stats of this façade.
+     *
+     * @return The top level package stats
+     */
+    PackageStats getTopLevelPackageStats() {
         return topLevelPackageStats;
     }
 
 
+    @Override
+    public JavaProjectMemoizer getLanguageSpecificProjectMemoizer() {
+        return memoizer;
+    }
+
+
     @Override
     protected MetricsComputer<ASTAnyTypeDeclaration, ASTMethodOrConstructorDeclaration> getLanguageSpecificComputer() {
         return JavaMetricsComputer.INSTANCE;

diff --git a/pmd-java/src/main/java/net/sourceforge/pmd/lang/java/metrics/JavaMetricsVisitor.java b/pmd-java/src/main/java/net/sourceforge/pmd/lang/java/metrics/JavaMetricsVisitor.java
@@ -10,6 +10,7 @@
 import net.sourceforge.pmd.lang.java.ast.ASTFieldDeclaration;
 import net.sourceforge.pmd.lang.java.ast.ASTMethodOrConstructorDeclaration;
 import net.sourceforge.pmd.lang.java.ast.JavaParserVisitorReducedAdapter;
+import net.sourceforge.pmd.lang.metrics.ProjectMemoizer;
 
 /**
  * Visitor for the metrics framework, that fills a {@link PackageStats} object with the signatures of operations and
@@ -19,12 +20,22 @@
  */
 class JavaMetricsVisitor extends JavaParserVisitorReducedAdapter {
 
-    private Stack<ClassStats> stack = new Stack<>();
+    private final Stack<ClassStats> stack = new Stack<>();
+    private final PackageStats toplevel;
+    private final ProjectMemoizer<ASTAnyTypeDeclaration, ASTMethodOrConstructorDeclaration> memoizer;
+
+
+    JavaMetricsVisitor(PackageStats toplevel, ProjectMemoizer<ASTAnyTypeDeclaration, ASTMethodOrConstructorDeclaration> memoizer) {
+        this.toplevel = toplevel;
+        this.memoizer = memoizer;
+    }
 
 
     @Override
     public Object visit(ASTAnyTypeDeclaration node, Object data) {
-        stack.push(((PackageStats) data).getClassStats(node.getQualifiedName(), true));
+        memoizer.addClassMemoizer(node.getQualifiedName());
+
+        stack.push(toplevel.getClassStats(node.getQualifiedName(), true));
         super.visit(node, data);
         stack.pop();
 
@@ -34,6 +45,8 @@ public Object visit(ASTAnyTypeDeclaration node, Object data) {
 
     @Override
     public Object visit(ASTMethodOrConstructorDeclaration node, Object data) {
+        memoizer.addOperationMemoizer(node.getQualifiedName());
+
         stack.peek().addOperation(node.getQualifiedName().getOperation(), node.getSignature());
         return super.visit(node, data);
     }

diff --git a/pmd-java/src/main/java/net/sourceforge/pmd/lang/java/metrics/JavaMetricsVisitorFacade.java b/pmd-java/src/main/java/net/sourceforge/pmd/lang/java/metrics/JavaMetricsVisitorFacade.java
@@ -15,8 +15,10 @@
 public class JavaMetricsVisitorFacade extends JavaParserVisitorAdapter {
 
     public void initializeWith(ASTCompilationUnit rootNode) {
-        JavaMetricsVisitor visitor = new JavaMetricsVisitor();
-        rootNode.jjtAccept(visitor, JavaMetrics.getTopLevelPackageStats());
+        JavaMetricsFacade facade = JavaMetrics.getFacade();
+        JavaMetricsVisitor visitor = new JavaMetricsVisitor(facade.getTopLevelPackageStats(),
+                                                            facade.getLanguageSpecificProjectMemoizer());
+        rootNode.jjtAccept(visitor, null);
     }
 
 }
diff --git a/pmd-java/src/main/java/net/sourceforge/pmd/lang/java/metrics/JavaProjectMemoizer.java b/pmd-java/src/main/java/net/sourceforge/pmd/lang/java/metrics/JavaProjectMemoizer.java
@@ -6,13 +6,13 @@
 
 import net.sourceforge.pmd.lang.java.ast.ASTAnyTypeDeclaration;
 import net.sourceforge.pmd.lang.java.ast.ASTMethodOrConstructorDeclaration;
-import net.sourceforge.pmd.lang.metrics.ProjectMemoizer;
+import net.sourceforge.pmd.lang.metrics.BasicProjectMemoizer;
 
 /**
- * Shorthand for a project mirror parameterized with Java-specific node types.
+ * Shorthand for a project memoizer parameterized with Java-specific node types.
  *
  * @author Clément Fournier
  */
-interface JavaProjectMemoizer extends ProjectMemoizer<ASTAnyTypeDeclaration, ASTMethodOrConstructorDeclaration> {
+class JavaProjectMemoizer extends BasicProjectMemoizer<ASTAnyTypeDeclaration, ASTMethodOrConstructorDeclaration> {
 
 }
diff --git a/pmd-java/src/main/java/net/sourceforge/pmd/lang/java/metrics/JavaSignatureMatcher.java b/pmd-java/src/main/java/net/sourceforge/pmd/lang/java/metrics/JavaSignatureMatcher.java
@@ -9,7 +9,7 @@
 import net.sourceforge.pmd.lang.java.metrics.signature.JavaOperationSigMask;
 
 /**
- * Gathers the methods that the Java project mirror should make available to metrics during the computation.
+ * Gathers the methods that PackageStats should make available to metrics during the computation.
  *
  * @author Clément Fournier
  */

diff --git a/pmd-java/src/main/java/net/sourceforge/pmd/lang/java/metrics/OperationStats.java b/pmd-java/src/main/java/net/sourceforge/pmd/lang/java/metrics/OperationStats.java
@@ -4,15 +4,12 @@
 
 package net.sourceforge.pmd.lang.java.metrics;
 
-import net.sourceforge.pmd.lang.java.ast.ASTMethodOrConstructorDeclaration;
-import net.sourceforge.pmd.lang.metrics.AbstractMetricMemoizer;
-
 /**
  * Statistics for an operation. Keeps a map of all memoized metrics results.
  *
  * @author Clément Fournier
  */
-class OperationStats extends AbstractMetricMemoizer<ASTMethodOrConstructorDeclaration> {
+class OperationStats {
 
     private final String name;