PARQUET-1170: Logical-type-based toString for proper representeation in tools/logs

parquet-cli/src/main/java/org/apache/parquet/cli/Util.java

@@ -27,15 +27,12 @@
 import org.apache.parquet.column.ColumnDescriptor;
 import org.apache.parquet.column.Encoding;
 import org.apache.parquet.column.EncodingStats;
-import org.apache.parquet.column.statistics.BinaryStatistics;
-import org.apache.parquet.column.statistics.BooleanStatistics;
 import org.apache.parquet.column.statistics.Statistics;
 import org.apache.parquet.hadoop.metadata.CompressionCodecName;
 import org.apache.parquet.schema.MessageType;
 import org.apache.parquet.schema.OriginalType;
 import org.apache.parquet.schema.PrimitiveType;
 import org.apache.parquet.schema.Type;
-import java.nio.charset.StandardCharsets;
 import java.util.Set;
 
 import static org.apache.parquet.column.Encoding.BIT_PACKED;
@@ -90,46 +87,15 @@ public static String minMaxAsString(Statistics stats, OriginalType annotation) {
     if (!stats.hasNonNullValue()) {
       return "";
     }
-    // TODO: use original types when showing decimal, timestamp, etc.
-    if (stats instanceof BinaryStatistics) {
-      byte[] minBytes = stats.getMinBytes();
-      byte[] maxBytes = stats.getMaxBytes();
-      return String.format("%s / %s",
-          printable(minBytes, annotation == OriginalType.UTF8, 30),
-          printable(maxBytes, annotation == OriginalType.UTF8, 30));
-    } else {
-      return String.format("%s / %s", stats.minAsString(), stats.maxAsString());
-    }
+    return String.format("%s / %s", humanReadable(stats.minAsString(), 30), humanReadable(stats.maxAsString(), 30));
   }
 
   public static String toString(Statistics stats, long count, OriginalType annotation) {
     if (stats == null) {
       return "no stats";
     }
-    // TODO: use original types when showing decimal, timestamp, etc.
-    if (stats instanceof BooleanStatistics) {
-      return String.format("nulls: %d/%d", stats.getNumNulls(), count);
-    } else if (stats instanceof BinaryStatistics) {
-      byte[] minBytes = stats.getMinBytes();
-      byte[] maxBytes = stats.getMaxBytes();
-      return String.format("min: %s max: %s nulls: %d/%d",
-          printable(minBytes, annotation == OriginalType.UTF8, 30),
-          printable(maxBytes, annotation == OriginalType.UTF8, 30),
-          stats.getNumNulls(), count);
-    } else {
-      return String.format("min: %s max: %s nulls: %d/%d",
-        stats.minAsString(), stats.maxAsString(), stats.getNumNulls(), count);
-    }
-  }
-
-  private static String printable(byte[] bytes, boolean isUtf8, int len) {
-    if (bytes == null) {
-      return "null";
-    } else if (isUtf8) {
-      return humanReadable(new String(bytes, StandardCharsets.UTF_8), len);
-    } else {
-      return humanReadable(bytes, len);
-    }
+    return String.format("min: %s max: %s nulls: %d/%d",
+        humanReadable(stats.minAsString(), 30), humanReadable(stats.maxAsString(), 30), stats.getNumNulls(), count);
   }
 
   public static String humanReadable(String str, int len) {

parquet-column/src/main/java/org/apache/parquet/column/statistics/BinaryStatistics.java

@@ -94,9 +94,8 @@ public byte[] getMinBytes() {
   }
 
   @Override
-  String toString(Binary value) {
-    // TODO: have separate toString for different logical types?
-    return value == null ? "null" : value.toStringUsingUTF8();
+  String stringify(Binary value) {
+    return stringifier.stringify(value);
   }
 
   @Override

parquet-column/src/main/java/org/apache/parquet/column/statistics/BooleanStatistics.java

@@ -87,6 +87,11 @@ public byte[] getMinBytes() {
     return BytesUtils.booleanToBytes(min);
   }
 
+  @Override
+  String stringify(Boolean value) {
+    return stringifier.stringify(value);
+  }
+
   @Override
   public boolean isSmallerThan(long size) {
     return !hasNonNullValue() || (2 < size);

parquet-column/src/main/java/org/apache/parquet/column/statistics/DoubleStatistics.java

@@ -88,8 +88,8 @@ public byte[] getMinBytes() {
   }
 
   @Override
-  String toString(Double value) {
-    return String.format("%.5f", value);
+  String stringify(Double value) {
+    return stringifier.stringify(value);
   }
 
   @Override

parquet-column/src/main/java/org/apache/parquet/column/statistics/FloatStatistics.java

@@ -89,8 +89,8 @@ public byte[] getMinBytes() {
   }
 
   @Override
-  String toString(Float value) {
-    return String.format("%.5f", value);
+  String stringify(Float value) {
+    return stringifier.stringify(value);
   }
 
   @Override

parquet-column/src/main/java/org/apache/parquet/column/statistics/IntStatistics.java

@@ -88,9 +88,8 @@ public byte[] getMinBytes() {
   }
 
   @Override
-  String toString(Integer value) {
-    // TODO: implement unsigned int as required
-    return value.toString();
+  String stringify(Integer value) {
+    return stringifier.stringify(value);
   }
 
   @Override

parquet-column/src/main/java/org/apache/parquet/column/statistics/LongStatistics.java

@@ -88,9 +88,8 @@ public byte[] getMinBytes() {
   }
 
   @Override
-  String toString(Long value) {
-    // TODO: implement unsigned int as required
-    return value.toString();
+  String stringify(Long value) {
+    return stringifier.stringify(value);
   }
 
   @Override

parquet-column/src/main/java/org/apache/parquet/column/statistics/Statistics.java

@@ -19,11 +19,10 @@
 package org.apache.parquet.column.statistics;
 
 import java.util.Arrays;
-import java.util.Objects;
-
 import org.apache.parquet.column.UnknownColumnTypeException;
 import org.apache.parquet.io.api.Binary;
 import org.apache.parquet.schema.PrimitiveComparator;
+import org.apache.parquet.schema.PrimitiveStringifier;
 import org.apache.parquet.schema.PrimitiveType;
 import org.apache.parquet.schema.PrimitiveType.PrimitiveTypeName;
 import org.apache.parquet.schema.Type;
@@ -40,10 +39,12 @@ public abstract class Statistics<T extends Comparable<T>> {
   private final PrimitiveComparator<T> comparator;
   private boolean hasNonNullValue;
   private long num_nulls;
+  final PrimitiveStringifier stringifier;
 
   Statistics(PrimitiveType type) {
     this.type = type;
     this.comparator = type.comparator();
+    this.stringifier = type.stringifier();
     hasNonNullValue = false;
     num_nulls = 0;
   }
@@ -287,19 +288,17 @@ public final int compareMaxToValue(T value) {
    * Returns the string representation of min for debugging/logging purposes.
    */
   public String minAsString() {
-    return toString(genericGetMin());
+    return stringify(genericGetMin());
   }
 
   /**
    * Returns the string representation of max for debugging/logging purposes.
    */
   public String maxAsString() {
-    return toString(genericGetMax());
+    return stringify(genericGetMax());
   }
 
-  String toString(T value) {
-    return Objects.toString(value);
-  }
+  abstract String stringify(T value);
 
   /**
    * Abstract method to return whether the min and max values fit in the given

parquet-column/src/main/java/org/apache/parquet/schema/OriginalType.java

@@ -21,24 +21,46 @@
 public enum OriginalType {
   MAP,
   LIST,
-  UTF8,
+  UTF8(PrimitiveStringifier.UTF8_STRINGIFIER),
   MAP_KEY_VALUE,
-  ENUM,
-  DECIMAL,
-  DATE,
-  TIME_MILLIS,
-  TIME_MICROS,
-  TIMESTAMP_MILLIS,
-  TIMESTAMP_MICROS,
-  UINT_8,
-  UINT_16,
-  UINT_32,
-  UINT_64,
-  INT_8,
-  INT_16,
-  INT_32,
-  INT_64,
-  JSON,
-  BSON,
-  INTERVAL;
+  ENUM(PrimitiveStringifier.UTF8_STRINGIFIER),
+  DECIMAL {
+    @Override
+    PrimitiveStringifier stringifier(PrimitiveType type) {
+      return PrimitiveStringifier.createDecimalStringifier(type.getDecimalMetadata().getScale());
+    }
+  },
+  DATE(PrimitiveStringifier.DATE_STRINGIFIER),
+  TIME_MILLIS(PrimitiveStringifier.TIME_STRINGIFIER),
+  TIME_MICROS(PrimitiveStringifier.TIME_STRINGIFIER),
+  TIMESTAMP_MILLIS(PrimitiveStringifier.TIMESTAMP_MILLIS_STRINGIFIER),
+  TIMESTAMP_MICROS(PrimitiveStringifier.TIMESTAMP_MICROS_STRINGIFIER),
+  UINT_8(PrimitiveStringifier.UNSIGNED_STRINGIFIER),
+  UINT_16(PrimitiveStringifier.UNSIGNED_STRINGIFIER),
+  UINT_32(PrimitiveStringifier.UNSIGNED_STRINGIFIER),
+  UINT_64(PrimitiveStringifier.UNSIGNED_STRINGIFIER),
+  INT_8(PrimitiveStringifier.DEFAULT_STRINGIFIER),
+  INT_16(PrimitiveStringifier.DEFAULT_STRINGIFIER),
+  INT_32(PrimitiveStringifier.DEFAULT_STRINGIFIER),
+  INT_64(PrimitiveStringifier.DEFAULT_STRINGIFIER),
+  JSON(PrimitiveStringifier.UTF8_STRINGIFIER),
+  BSON(PrimitiveStringifier.DEFAULT_STRINGIFIER),
+  INTERVAL(PrimitiveStringifier.INTERVAL_STRINGIFIER);
+
+  private final PrimitiveStringifier stringifier;
+
+  PrimitiveStringifier stringifier(PrimitiveType type) {
+    if (stringifier == null) {
+      throw new UnsupportedOperationException("Stringifier is not supported for the original type: " + this);
+    }
+    return stringifier;
+  }
+
+  OriginalType() {
+    this(null);
+  }
+
+  OriginalType(PrimitiveStringifier stringifier) {
+    this.stringifier = stringifier;
+  }
 }