Merge pull request #1572 from youtube/caseInsensitiveMap

Case Insensitive Map for getting Column Index

java/client/pom.xml

@@ -20,6 +20,11 @@
       <artifactId>jsr305</artifactId>
       <version>3.0.0</version>
     </dependency>
+    <dependency>
+      <groupId>org.apache.commons</groupId>
+      <artifactId>commons-collections4</artifactId>
+      <version>4.1</version>
+    </dependency>
   </dependencies>
 
   <pluginRepositories>

java/client/src/main/java/com/youtube/vitess/client/cursor/FieldMap.java

@@ -4,10 +4,11 @@ import static com.google.common.base.Preconditions.checkArgument;
 import static com.google.common.base.Preconditions.checkNotNull;
 
 import com.google.common.collect.ImmutableList;
-import com.google.common.collect.ImmutableMap;
 
 import com.youtube.vitess.proto.Query.Field;
 
+import org.apache.commons.collections4.map.CaseInsensitiveMap;
+
 import java.util.List;
 import java.util.Map;
 
@@ -16,6 +17,9 @@ import javax.annotation.Nullable;
 /**
  * A wrapper for {@code List<Field>} that also facilitates lookup by field name.
  *
+ * <p>Lookups by field name are case-insensitive, as in {@link java.sql.ResultSet}.
+ * If multiple fields have the same name, the earliest one will be returned.
+ *
  * <p>The field name maps to an index, rather than a Field, because that same
  * index is also used to find the value in a separate list.
  */
@@ -26,25 +30,43 @@ public class FieldMap {
   public FieldMap(Iterable<Field> fields) {
     this.fields = ImmutableList.copyOf(checkNotNull(fields));
 
-    ImmutableMap.Builder<String, Integer> builder = new ImmutableMap.Builder<>();
+    indexMap = new CaseInsensitiveMap<String, Integer>();
     // columnIndex is 1-based.
     int columnIndex = 1;
     for (Field field : this.fields) {
-      builder.put(field.getName(), columnIndex++);
+      String columnLabel = field.getName();
+      // If multiple columns have the same name,
+      // prefer the earlier one as JDBC ResultSet does.
+      if (!indexMap.containsKey(columnLabel)) {
+        indexMap.put(columnLabel, columnIndex);
+      }
+      ++columnIndex;
     }
-    indexMap = builder.build();
   }
 
   public List<Field> getList() {
     return fields;
   }
 
+  /**
+   * Returns the {@link Field} for a 1-based column index.
+   *
+   * @param columnIndex 1-based column number (0 is invalid)
+   */
   public Field get(int columnIndex) {
     // columnIndex is 1-based.
     checkArgument(columnIndex >= 1, "columnIndex out of range: %s", columnIndex);
     return fields.get(columnIndex - 1);
   }
 
+  /**
+   * Returns the 1-based index for a column label.
+   *
+   * <p>If multiple columns have the same label,
+   * the earlier one is returned.
+   *
+   * @param columnLabel case-insensitive column label
+   */
   @Nullable
   public Integer getIndex(String columnLabel) {
     return indexMap.get(columnLabel);

java/client/src/main/java/com/youtube/vitess/client/cursor/Row.java

@@ -33,10 +33,12 @@ import javax.annotation.concurrent.NotThreadSafe;
  * the list of {@link Field}s from the corresponding
  * {@link com.youtube.vitess.proto.Query.QueryResult}.
  *
- * <p>Note that {@code columnIndex} values start at 1 for the first column,
- * since the methods on {@code Row} are intended to be compatible with those
- * on {@link java.sql.ResultSet} (which uses 1-based {@code columnIndex})
- * where possible.
+ * <p>Methods on {@code Row} are intended to be compatible with those on
+ * {@link java.sql.ResultSet} where possible.
+ * This means {@code columnIndex} values start at 1 for the first column,
+ * and {@code columnLabel} values are case-insensitive. If multiple columns
+ * have the same case-insensitive {@code columnLabel}, the earliest one will
+ * be returned.
  */
 @NotThreadSafe
 public class Row {
@@ -115,6 +117,8 @@ public class Row {
 
   /**
    * Returns 1-based column number.
+   *
+   * @param columnLabel case-insensitive column label
    */
   public int findColumn(String columnLabel) throws SQLException {
     Integer columnIndex = fieldMap.getIndex(columnLabel);
@@ -124,6 +128,9 @@ public class Row {
     return columnIndex;
   }
 
+  /**
+   * @param columnLabel case-insensitive column label
+   */
   public Object getObject(String columnLabel) throws SQLException {
     return getObject(findColumn(columnLabel));
   }
@@ -161,6 +168,8 @@ public class Row {
    *
    * <p>To distinguish between 0 and SQL NULL, use either {@link #wasNull()}
    * or {@link #getObject(String,Class)}.
+   *
+   * @param columnLabel case-insensitive column label
    */
   public int getInt(String columnLabel) throws SQLException {
     return getInt(findColumn(columnLabel));
@@ -179,6 +188,9 @@ public class Row {
     return value == null ? 0 : value;
   }
 
+  /**
+   * @param columnLabel case-insensitive column label
+   */
   public UnsignedLong getULong(String columnLabel) throws SQLException {
     return getULong(findColumn(columnLabel));
   }
@@ -190,6 +202,9 @@ public class Row {
     return getObject(columnIndex, UnsignedLong.class);
   }
 
+  /**
+   * @param columnLabel case-insensitive column label
+   */
   public String getString(String columnLabel) throws SQLException {
     return getString(findColumn(columnLabel));
   }
@@ -206,6 +221,8 @@ public class Row {
    *
    * <p>To distinguish between 0 and SQL NULL, use either {@link #wasNull()}
    * or {@link #getObject(String,Class)}.
+   *
+   * @param columnLabel case-insensitive column label
    */
   public long getLong(String columnLabel) throws SQLException {
     return getLong(findColumn(columnLabel));
@@ -229,6 +246,8 @@ public class Row {
    *
    * <p>To distinguish between 0 and SQL NULL, use either {@link #wasNull()}
    * or {@link #getObject(String,Class)}.
+   *
+   * @param columnLabel case-insensitive column label
    */
   public double getDouble(String columnLabel) throws SQLException {
     return getDouble(findColumn(columnLabel));
@@ -252,6 +271,8 @@ public class Row {
    *
    * <p>To distinguish between 0 and SQL NULL, use either {@link #wasNull()}
    * or {@link #getObject(String,Class)}.
+   *
+   * @param columnLabel case-insensitive column label
    */
   public float getFloat(String columnLabel) throws SQLException {
     return getFloat(findColumn(columnLabel));
@@ -272,6 +293,8 @@ public class Row {
 
   /**
    * Returns the column value as a {@link Date} with the default time zone.
+   *
+   * @param columnLabel case-insensitive column label
    */
   public Date getDate(String columnLabel) throws SQLException {
     return getDate(findColumn(columnLabel), Calendar.getInstance());
@@ -279,6 +302,8 @@ public class Row {
 
   /**
    * Returns the column value as a {@link Date} with the given {@link Calendar}.
+   *
+   * @param columnLabel case-insensitive column label
    */
   public Date getDate(String columnLabel, Calendar cal) throws SQLException {
     return getDate(findColumn(columnLabel), cal);
@@ -317,6 +342,8 @@ public class Row {
 
   /**
    * Returns the column value as {@link Time} with the default time zone.
+   *
+   * @param columnLabel case-insensitive column label
    */
   public Time getTime(String columnLabel) throws SQLException {
     return getTime(findColumn(columnLabel), Calendar.getInstance());
@@ -324,6 +351,8 @@ public class Row {
 
   /**
    * Returns the column value as {@link Time} with the given {@link Calendar}.
+   *
+   * @param columnLabel case-insensitive column label
    */
   public Time getTime(String columnLabel, Calendar cal) throws SQLException {
     return getTime(findColumn(columnLabel), cal);
@@ -362,6 +391,8 @@ public class Row {
 
   /**
    * Returns the column value as {@link Timestamp} with the default time zone.
+   *
+   * @param columnLabel case-insensitive column label
    */
   public Timestamp getTimestamp(String columnLabel) throws SQLException {
     return getTimestamp(findColumn(columnLabel), Calendar.getInstance());
@@ -369,6 +400,8 @@ public class Row {
 
   /**
    * Returns the column value as {@link Timestamp} with the given {@link Calendar}.
+   *
+   * @param columnLabel case-insensitive column label
    */
   public Timestamp getTimestamp(String columnLabel, Calendar cal) throws SQLException {
     return getTimestamp(findColumn(columnLabel), cal);
@@ -410,6 +443,9 @@ public class Row {
     }
   }
 
+  /**
+   * @param columnLabel case-insensitive column label
+   */
   public byte[] getBytes(String columnLabel) throws SQLException {
     return getBytes(findColumn(columnLabel));
   }
@@ -421,6 +457,9 @@ public class Row {
     return getObject(columnIndex, byte[].class);
   }
 
+  /**
+   * @param columnLabel case-insensitive column label
+   */
   public BigDecimal getBigDecimal(String columnLabel) throws SQLException {
     return getBigDecimal(findColumn(columnLabel));
   }
@@ -437,6 +476,8 @@ public class Row {
    *
    * <p>To distinguish between 0 and SQL NULL, use either {@link #wasNull()}
    * or {@link #getObject(String,Class)}.
+   *
+   * @param columnLabel case-insensitive column label
    */
   public short getShort(String columnLabel) throws SQLException {
     return getShort(findColumn(columnLabel));
@@ -494,6 +535,7 @@ public class Row {
    * }
    * </pre></blockquote>
    *
+   * @param columnLabel case-insensitive column label
    * @throws SQLDataException if the type doesn't match the actual value.
    */
   public <T> T getObject(String columnLabel, Class<T> type) throws SQLException {

java/client/src/test/java/com/youtube/vitess/client/cursor/CursorTest.java

@@ -32,12 +32,13 @@ public class CursorTest {
             new SimpleCursor(
                 QueryResult.newBuilder()
                     .addFields(Field.newBuilder().setName("col1").build())
-                    .addFields(Field.newBuilder().setName("col2").build())
-                    .addFields(Field.newBuilder().setName("col3").build())
+                    .addFields(Field.newBuilder().setName("COL2").build()) // case-insensitive
+                    .addFields(Field.newBuilder().setName("col1").build()) // duplicate
+                    .addFields(Field.newBuilder().setName("col4").build()) // skip duplicate
                     .build())) {
-      Assert.assertEquals(1, cursor.findColumn("col1"));
-      Assert.assertEquals(2, cursor.findColumn("col2"));
-      Assert.assertEquals(3, cursor.findColumn("col3"));
+      Assert.assertEquals(1, cursor.findColumn("col1")); // should return first col1
+      Assert.assertEquals(2, cursor.findColumn("Col2")); // should be case-insensitive
+      Assert.assertEquals(4, cursor.findColumn("col4")); // index should skip over duplicate
     }
   }