[HUDI-4391] Incremental read from archived commits for flink (#6096)

hudi-common/src/main/java/org/apache/hudi/common/table/log/InstantRange.java

@@ -19,6 +19,7 @@
 package org.apache.hudi.common.table.log;
 
 import org.apache.hudi.common.table.timeline.HoodieTimeline;
+import org.apache.hudi.common.util.ValidationUtils;
 
 import java.io.Serializable;
 import java.util.Objects;
@@ -33,19 +34,15 @@ public abstract class InstantRange implements Serializable {
   protected final String endInstant;
 
   public InstantRange(String startInstant, String endInstant) {
-    this.startInstant = Objects.requireNonNull(startInstant);
-    this.endInstant = Objects.requireNonNull(endInstant);
+    this.startInstant = startInstant;
+    this.endInstant = endInstant;
   }
 
-  public static InstantRange getInstance(String startInstant, String endInstant, RangeType rangeType) {
-    switch (rangeType) {
-      case OPEN_CLOSE:
-        return new OpenCloseRange(startInstant, endInstant);
-      case CLOSE_CLOSE:
-        return new CloseCloseRange(startInstant, endInstant);
-      default:
-        throw new AssertionError();
-    }
+  /**
+   * Returns the builder.
+   */
+  public static Builder builder() {
+    return new Builder();
   }
 
   public String getStartInstant() {
@@ -65,14 +62,14 @@ public abstract class InstantRange implements Serializable {
   /**
    * Represents a range type.
    */
-  public enum RangeType {
+  public static enum RangeType {
     OPEN_CLOSE, CLOSE_CLOSE
   }
 
   private static class OpenCloseRange extends InstantRange {
 
     public OpenCloseRange(String startInstant, String endInstant) {
-      super(startInstant, endInstant);
+      super(Objects.requireNonNull(startInstant), endInstant);
     }
 
     @Override
@@ -84,10 +81,31 @@ public abstract class InstantRange implements Serializable {
     }
   }
 
+  private static class OpenCloseRangeNullableBoundary extends InstantRange {
+
+    public OpenCloseRangeNullableBoundary(String startInstant, String endInstant) {
+      super(startInstant, endInstant);
+      ValidationUtils.checkArgument(startInstant != null || endInstant != null,
+          "Start and end instants can not both be null");
+    }
+
+    @Override
+    public boolean isInRange(String instant) {
+      if (startInstant == null) {
+        return HoodieTimeline.compareTimestamps(instant, HoodieTimeline.LESSER_THAN_OR_EQUALS, endInstant);
+      } else if (endInstant == null) {
+        return HoodieTimeline.compareTimestamps(instant, HoodieTimeline.GREATER_THAN, startInstant);
+      } else {
+        return HoodieTimeline.compareTimestamps(instant, HoodieTimeline.GREATER_THAN, startInstant)
+            && HoodieTimeline.compareTimestamps(instant, HoodieTimeline.LESSER_THAN_OR_EQUALS, endInstant);
+      }
+    }
+  }
+
   private static class CloseCloseRange extends InstantRange {
 
     public CloseCloseRange(String startInstant, String endInstant) {
-      super(startInstant, endInstant);
+      super(Objects.requireNonNull(startInstant), endInstant);
     }
 
     @Override
@@ -98,4 +116,78 @@ public abstract class InstantRange implements Serializable {
       return HoodieTimeline.compareTimestamps(instant, HoodieTimeline.GREATER_THAN_OR_EQUALS, startInstant);
     }
   }
+
+  private static class CloseCloseRangeNullableBoundary extends InstantRange {
+
+    public CloseCloseRangeNullableBoundary(String startInstant, String endInstant) {
+      super(startInstant, endInstant);
+      ValidationUtils.checkArgument(startInstant != null || endInstant != null,
+          "Start and end instants can not both be null");
+    }
+
+    @Override
+    public boolean isInRange(String instant) {
+      if (startInstant == null) {
+        return HoodieTimeline.compareTimestamps(instant, HoodieTimeline.LESSER_THAN_OR_EQUALS, endInstant);
+      } else if (endInstant == null) {
+        return HoodieTimeline.compareTimestamps(instant, HoodieTimeline.GREATER_THAN_OR_EQUALS, startInstant);
+      } else {
+        return HoodieTimeline.compareTimestamps(instant, HoodieTimeline.GREATER_THAN_OR_EQUALS, startInstant)
+            && HoodieTimeline.compareTimestamps(instant, HoodieTimeline.LESSER_THAN_OR_EQUALS, endInstant);
+      }
+    }
+  }
+
+  // -------------------------------------------------------------------------
+  //  Inner Class
+  // -------------------------------------------------------------------------
+
+  /**
+   * Builder for {@link InstantRange}.
+   */
+  public static class Builder {
+    private String startInstant;
+    private String endInstant;
+    private RangeType rangeType;
+    private boolean nullableBoundary = false;
+
+    private Builder() {
+    }
+
+    public Builder startInstant(String startInstant) {
+      this.startInstant = startInstant;
+      return this;
+    }
+
+    public Builder endInstant(String endInstant) {
+      this.endInstant = endInstant;
+      return this;
+    }
+
+    public Builder rangeType(RangeType rangeType) {
+      this.rangeType = rangeType;
+      return this;
+    }
+
+    public Builder nullableBoundary(boolean nullable) {
+      this.nullableBoundary = nullable;
+      return this;
+    }
+
+    public InstantRange build() {
+      ValidationUtils.checkState(this.rangeType != null, "Range type is required");
+      switch (rangeType) {
+        case OPEN_CLOSE:
+          return nullableBoundary
+              ? new OpenCloseRangeNullableBoundary(startInstant, endInstant)
+              : new OpenCloseRange(startInstant, endInstant);
+        case CLOSE_CLOSE:
+          return nullableBoundary
+              ? new CloseCloseRangeNullableBoundary(startInstant, endInstant)
+              : new CloseCloseRange(startInstant, endInstant);
+        default:
+          throw new AssertionError();
+      }
+    }
+  }
 }