[#163] Added ByteString.iterator(max), with tests

susanw1 · Sep 12, 2024 · 56ebf58 · 56ebf58
1 parent bca99d4
commit 56ebf58
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Showing 3 changed files with 28 additions and 8 deletions.
diff --git a/util/misc/src/main/java/net/zscript/ascii/TextBox.java b/util/misc/src/main/java/net/zscript/ascii/TextBox.java
@@ -5,7 +5,6 @@
 import java.util.Iterator;
 import java.util.List;
 import java.util.NoSuchElementException;
-import java.util.PrimitiveIterator;
 
 public class TextBox implements AsciiFrame {
 
@@ -133,7 +132,7 @@ public boolean setWidth(int width) {
     @Override
     public Iterator<TextRow> iterator() {
         emptyBuilder();
-        return new Iterator<TextRow>() {
+        return new Iterator<>() {
             private final Iterator<TextLine> lineIter = lines.iterator();
 
             private int indent = 0;

diff --git a/util/misc/src/main/java/net/zscript/util/ByteString.java b/util/misc/src/main/java/net/zscript/util/ByteString.java
@@ -36,13 +36,23 @@ public int size() {
     }
 
     /**
-     * Returns a block Iterator over the bytes in the string.
+     * Returns a block Iterator over the bytes in the string, with the default maximum block size set to the size of this ByteString.
      *
      * @return iterator a block iterator
      */
     @Override
     public BlockIterator iterator() {
-        return new ByteBlockIterator();
+        return new ByteBlockIterator(bytes.length);
+    }
+
+    /**
+     * Returns a block Iterator over the bytes in the string, with the specified default maximum block size.
+     *
+     * @param defaultMaxLength the max number of bytes to return in a call to {@link BlockIterator#nextContiguous()}
+     * @return iterator a block iterator
+     */
+    public BlockIterator iterator(int defaultMaxLength) {
+        return new ByteBlockIterator(defaultMaxLength);
     }
 
     /**
@@ -612,8 +622,18 @@ default ByteString toByteString(T object) {
      * Simple array iterator
      */
     private class ByteBlockIterator implements BlockIterator {
+        final int defaultMaxLength;
         int index = 0;
 
+        /**
+         * Creates a new iterator.
+         *
+         * @param defaultMaxLength the max number of bytes to return in a call to {@link #nextContiguous()}
+         */
+        ByteBlockIterator(int defaultMaxLength) {
+            this.defaultMaxLength = defaultMaxLength;
+        }
+
         @Override
         public boolean hasNext() {
             return index < bytes.length;
@@ -629,7 +649,7 @@ public Byte next() {
 
         @Override
         public byte[] nextContiguous() {
-            return nextContiguous(bytes.length);
+            return nextContiguous(defaultMaxLength);
         }
 
         @Override

diff --git a/util/misc/src/test/java/net/zscript/util/ByteStringTest.java b/util/misc/src/test/java/net/zscript/util/ByteStringTest.java
@@ -71,15 +71,16 @@ public void shouldIterateBytes() {
     @Test
     public void shouldIterateBlockBytes() {
         var str  = ByteString.builder().appendUtf8("hello, London calling, £5 is a fiver").build();
-        var iter = str.iterator();
+        var iter = str.iterator(6);
 
         assertThat(iter.hasNext()).isTrue();
         assertThat(iter.next()).isEqualTo((byte) 'h');
         assertThat(iter.nextContiguous(8)).isEqualTo("ello, Lo".getBytes(ISO_8859_1));
         assertThat(iter.nextContiguous(11)).isEqualTo("ndon callin".getBytes(ISO_8859_1));
-        assertThat(iter.nextContiguous(6)).containsExactly('g', ',', ' ', 0xc2, 0xa3, '5');
+        assertThat(iter.nextContiguous()).containsExactly('g', ',', ' ', 0xc2, 0xa3, '5');
         assertThat(iter.hasNext()).isTrue();
-        assertThat(iter.nextContiguous()).isEqualTo(" is a fiver".getBytes(ISO_8859_1));
+        assertThat(iter.nextContiguous()).isEqualTo(" is a ".getBytes(ISO_8859_1));
+        assertThat(iter.nextContiguous()).isEqualTo("fiver".getBytes(ISO_8859_1));
         assertThat(iter.hasNext()).isFalse();
     }