Introduce FullyQualifiedName in SPI

presto-spi/src/main/java/com/facebook/presto/spi/relation/FullyQualifiedName.java

@@ -0,0 +1,158 @@
+/*
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.facebook.presto.spi.relation;
+
+import com.fasterxml.jackson.annotation.JsonCreator;
+import com.fasterxml.jackson.annotation.JsonValue;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import static java.util.Arrays.asList;
+import static java.util.Collections.unmodifiableList;
+import static java.util.Locale.ENGLISH;
+import static java.util.Objects.requireNonNull;
+
+public class FullyQualifiedName
+{
+    private final List<String> parts;
+    private final List<String> originalParts;
+
+    @JsonCreator
+    public static FullyQualifiedName of(String dottedName)
+    {
+        String[] parts = dottedName.split("\\.");
+        if (parts.length < 3) {
+            throw new IllegalArgumentException("FullyQualifiedName should be in the form of 'a.b.c' and have at least 3 parts");
+        }
+        return of(asList(parts));
+    }
+
+    public static FullyQualifiedName of(String part1, String part2, String part3, String... rest)
+    {
+        List<String> parts = new ArrayList<>(rest.length + 3);
+        parts.add(part1);
+        parts.add(part2);
+        parts.add(part3);
+        parts.addAll(asList(rest));
+        return of(parts);
+    }
+
+    public static FullyQualifiedName of(List<String> originalParts)
+    {
+        requireNonNull(originalParts, "originalParts is null");
+        if (originalParts.size() < 3) {
+            throw new IllegalArgumentException("originalParts should have at least 3 parts");
+        }
+
+        List<String> parts = new ArrayList<>(originalParts.size());
+        for (String originalPart : originalParts) {
+            parts.add(originalPart.toLowerCase(ENGLISH));
+        }
+
+        return new FullyQualifiedName(originalParts, parts);
+    }
+
+    public static FullyQualifiedName of(FullyQualifiedName.Prefix prefix, String name)
+    {
+        List<String> parts = new ArrayList<>(prefix.parts);
+        parts.add(name);
+        return of(parts);
+    }
+
+    private FullyQualifiedName(List<String> originalParts, List<String> parts)
+    {
+        this.originalParts = unmodifiableList(originalParts);
+        this.parts = unmodifiableList(parts);
+    }
+
+    public List<String> getParts()
+    {
+        return parts;
+    }
+
+    public List<String> getOriginalParts()
+    {
+        return originalParts;
+    }
+
+    public String getSuffix()
+    {
+        return parts.get(parts.size() - 1);
+    }
+
+    public Prefix getPrefix()
+    {
+        return new Prefix(parts.subList(0, parts.size() - 1));
+    }
+
+    @JsonValue
+    @Override
+    public String toString()
+    {
+        return String.join(".", parts);
+    }
+
+    @Override
+    public boolean equals(Object o)
+    {
+        if (this == o) {
+            return true;
+        }
+        if (o == null || getClass() != o.getClass()) {
+            return false;
+        }
+        return parts.equals(((FullyQualifiedName) o).parts);
+    }
+
+    @Override
+    public int hashCode()
+    {
+        return parts.hashCode();
+    }
+
+    public static class Prefix
+    {
+        private final List<String> parts;
+
+        private Prefix(List<String> parts)
+        {
+            this.parts = unmodifiableList(parts);
+        }
+
+        @Override
+        public String toString()
+        {
+            return String.join(".", parts);
+        }
+
+        @Override
+        public boolean equals(Object o)
+        {
+            if (this == o) {
+                return true;
+            }
+            if (o == null || getClass() != o.getClass()) {
+                return false;
+            }
+            return parts.equals(((FullyQualifiedName.Prefix) o).parts);
+        }
+
+        @Override
+        public int hashCode()
+        {
+            return parts.hashCode();
+        }
+    }
+}