Eliminate unneeded YangLocationPath subclasses

*WithSteps subclasses are not that helpful, as we only have single
onjects which do not have steps. Integrate steps into YangLocationPath,
making it bimorphic (and its getSteps() method monomorphic).

Also clean up arguments/returns, so that we propagate only Immutable
collections.

Change-Id: Ie0cdd2fb558b0b51071fd49eded9bfa1f6e20b1b
Signed-off-by: Robert Varga <robert.varga@pantheon.tech>

diff --git a/yang/yang-xpath-api/src/main/java/org/opendaylight/yangtools/yang/xpath/api/YangLocationPath.java b/yang/yang-xpath-api/src/main/java/org/opendaylight/yangtools/yang/xpath/api/YangLocationPath.java
index 973070b904d8b14e59c19b38eb311422388025fb..b3e687e966155c920256253a93490b22feb07a19 100644 (file)
--- a/yang/yang-xpath-api/src/main/java/org/opendaylight/yangtools/yang/xpath/api/YangLocationPath.java
+++ b/yang/yang-xpath-api/src/main/java/org/opendaylight/yangtools/yang/xpath/api/YangLocationPath.java
@@ -13,11 +13,11 @@ import com.google.common.annotations.Beta;
 import com.google.common.base.MoreObjects;
 import com.google.common.base.MoreObjects.ToStringHelper;
 import com.google.common.collect.ImmutableList;
+import com.google.common.collect.ImmutableSet;
 import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
 import java.io.Serializable;
 import java.util.Arrays;
 import java.util.Collection;
-import java.util.List;
 import java.util.Objects;
 import java.util.Set;
 import org.eclipse.jdt.annotation.Nullable;
@@ -94,15 +94,15 @@ public class YangLocationPath implements YangExpr {
     static final class AxisStepWithPredicates extends AxisStep {
         private static final long serialVersionUID = 1L;
 
-        private final Set<YangExpr> predicates;
+        private final ImmutableSet<YangExpr> predicates;
 
-        AxisStepWithPredicates(final YangXPathAxis axis, final Set<YangExpr> predicates) {
+        AxisStepWithPredicates(final YangXPathAxis axis, final ImmutableSet<YangExpr> predicates) {
             super(axis);
             this.predicates = requireNonNull(predicates);
         }
 
         @Override
-        public Set<YangExpr> getPredicates() {
+        public ImmutableSet<YangExpr> getPredicates() {
             return predicates;
         }
     }
@@ -187,15 +187,15 @@ public class YangLocationPath implements YangExpr {
     static final class QNameStepWithPredicates extends QNameStep {
         private static final long serialVersionUID = 1L;
 
-        private final Set<YangExpr> predicates;
+        private final ImmutableSet<YangExpr> predicates;
 
-        QNameStepWithPredicates(final YangXPathAxis axis, final QName qname, final Set<YangExpr> predicates) {
+        QNameStepWithPredicates(final YangXPathAxis axis, final QName qname, final ImmutableSet<YangExpr> predicates) {
             super(axis, qname);
             this.predicates = requireNonNull(predicates);
         }
 
         @Override
-        public Set<YangExpr> getPredicates() {
+        public ImmutableSet<YangExpr> getPredicates() {
             return predicates;
         }
     }
@@ -243,16 +243,16 @@ public class YangLocationPath implements YangExpr {
     static final class NodeTypeStepWithPredicates extends NodeTypeStep {
         private static final long serialVersionUID = 1L;
 
-        private final Set<YangExpr> predicates;
+        private final ImmutableSet<YangExpr> predicates;
 
         NodeTypeStepWithPredicates(final YangXPathAxis axis, final YangXPathNodeType type,
-                final Set<YangExpr> predicates) {
+                final ImmutableSet<YangExpr> predicates) {
             super(axis, type);
             this.predicates = requireNonNull(predicates);
         }
 
         @Override
-        public Set<YangExpr> getPredicates() {
+        public ImmutableSet<YangExpr> getPredicates() {
             return predicates;
         }
     }
@@ -290,65 +290,41 @@ public class YangLocationPath implements YangExpr {
     static final class ProcessingInstructionStepWithPredicates extends ProcessingInstructionStep {
         private static final long serialVersionUID = 1L;
 
-        private final Set<YangExpr> predicates;
+        private final ImmutableSet<YangExpr> predicates;
 
         ProcessingInstructionStepWithPredicates(final YangXPathAxis axis, final String name,
-                final Set<YangExpr> predicates) {
+                final ImmutableSet<YangExpr> predicates) {
             super(axis, name);
             this.predicates = requireNonNull(predicates);
         }
 
         @Override
-        public Set<YangExpr> getPredicates() {
+        public ImmutableSet<YangExpr> getPredicates() {
             return predicates;
         }
     }
 
-    public static class Absolute extends YangLocationPath {
+    public static final class Absolute extends YangLocationPath {
         private static final long serialVersionUID = 1L;
 
-        @Override
-        public final boolean isAbsolute() {
-            return true;
-        }
-    }
-
-    private static final class AbsoluteWithSteps extends Absolute {
-        private static final long serialVersionUID = 1L;
-
-        private final List<Step> steps;
-
-        AbsoluteWithSteps(final List<Step> steps) {
-            this.steps = requireNonNull(steps);
+        Absolute(final ImmutableList<Step> steps) {
+            super(steps);
         }
 
         @Override
-        public List<Step> getSteps() {
-            return steps;
-        }
-    }
-
-    private static final class WithSteps extends YangLocationPath {
-        private static final long serialVersionUID = 1L;
-
-        private final List<Step> steps;
-
-        WithSteps(final List<Step> steps) {
-            this.steps = requireNonNull(steps);
-        }
-
-        @Override
-        public List<Step> getSteps() {
-            return steps;
+        public boolean isAbsolute() {
+            return true;
         }
     }
 
     private static final long serialVersionUID = 1L;
-    private static final YangLocationPath ROOT = new Absolute();
-    private static final YangLocationPath SELF = new YangLocationPath();
+    private static final YangLocationPath ROOT = new Absolute(ImmutableList.of());
+    private static final YangLocationPath SELF = new YangLocationPath(ImmutableList.of());
+
+    private final ImmutableList<Step> steps;
 
-    YangLocationPath() {
-        // Hidden to prevent external instantiation
+    YangLocationPath(final ImmutableList<Step> steps) {
+        this.steps = requireNonNull(steps);
     }
 
     public static final YangLocationPath of(final boolean absolute) {
@@ -364,8 +340,8 @@ public class YangLocationPath implements YangExpr {
             return of(absolute);
         }
 
-        final List<Step> copy = ImmutableList.copyOf(steps);
-        return absolute ? new AbsoluteWithSteps(copy) : new WithSteps(copy);
+        final ImmutableList<Step> copy = ImmutableList.copyOf(steps);
+        return absolute ? new Absolute(copy) : new YangLocationPath(copy);
     }
 
     /**
@@ -391,13 +367,13 @@ public class YangLocationPath implements YangExpr {
         return false;
     }
 
-    public List<Step> getSteps() {
-        return ImmutableList.of();
+    public final ImmutableList<Step> getSteps() {
+        return steps;
     }
 
     @Override
     public final int hashCode() {
-        return Boolean.hashCode(isAbsolute()) * 31 + getSteps().hashCode();
+        return Boolean.hashCode(isAbsolute()) * 31 + steps.hashCode();
     }
 
     @Override
@@ -409,17 +385,19 @@ public class YangLocationPath implements YangExpr {
             return false;
         }
         final YangLocationPath other = (YangLocationPath) obj;
-        return isAbsolute() == other.isAbsolute() && getSteps().equals(other.getSteps());
+        return isAbsolute() == other.isAbsolute() && steps.equals(other.steps);
     }
 
     @Override
     public final String toString() {
-        final ToStringHelper helper = MoreObjects.toStringHelper(YangLocationPath.class);
-        helper.add("absolute", isAbsolute());
-        final List<Step> steps = getSteps();
+        final ToStringHelper helper = MoreObjects.toStringHelper(YangLocationPath.class).add("absolute", isAbsolute());
         if (!steps.isEmpty()) {
             helper.add("steps", steps);
         }
         return helper.toString();
     }
+
+    final Object readSolve() {
+        return steps.isEmpty() ? of(isAbsolute()) : this;
+    }
 }