Add stream() method to Table

core/src/main/java/tech/tablesaw/api/Table.java

@@ -25,8 +25,11 @@
 import java.util.List;
 import java.util.function.Consumer;
 import java.util.function.Predicate;
+import java.util.stream.Stream;
 
 import com.google.common.base.Preconditions;
+import com.google.common.collect.Iterators;
+import com.google.common.collect.Streams;
 import com.google.common.primitives.Ints;
 
 import io.github.classgraph.ClassGraph;
@@ -1024,50 +1027,35 @@ public boolean hasNext() {
         };
     }
 
+    public Stream<Row> stream() {
+      return Streams.stream(iterator());
+    }
+
     /**
      * Applies the operation in {@code doable} to every row in the table
+     * @deprecated use {@code stream().forEach}
      */
     public void doWithRows(Consumer<Row> doable) {
-        Row row = new Row(this);
-        while (row.hasNext()) {
-            doable.accept(row.next());
-        }
+      stream().forEach(doable);
     }
 
     /**
      * Applies the predicate to each row, and return true if any row returns true
+     * @deprecated use {@code stream().anyMatch}
      */
     public boolean detect(Predicate<Row> predicate) {
-        Row row = new Row(this);
-        while (row.hasNext()) {
-            if (predicate.test(row.next())) {
-                return true;
-            }
-        }
-        return false;
+        return stream().anyMatch(predicate);
     }
 
     /**
      * Applies the operation in {@code rowConsumer} to every series of n rows in the table
+     * @deprecated use {@code Streams.stream(Iterators.partition(iterator(), n)).forEach}
      */
     public void stepWithRows(Consumer<Row[]> rowConsumer, int n) {
-        if (isEmpty()) {
-            return;
-        }
-        Row[] rows = new Row[n];
-        for (int i = 0; i < n; i++) {
-            rows[i] = new Row(this);
-        }
-
-        int max = rowCount() / n;
-
-        for (int i = 0; i < max; i++) {  //0, 1
-            for (int r = 1; r <= n; r++) {
-                int row = i*n + r - 1;
-                rows[r-1].at(row);
-            }
-            rowConsumer.accept(rows);
-        }
+        Streams
+            .stream(Iterators.partition(iterator(), n))
+            .map(list -> list.toArray(new Row[list.size()]))
+            .forEach(rowConsumer);
     }
 
     /**