Bytes has signed and unsigned comparators

changelog/@unreleased/pr-2102.v2.yml

@@ -0,0 +1,5 @@
+type: improvement
+improvement:
+  description: Bytes has signed and unsigned comparators
+  links:
+  - https://github.com/palantir/conjure-java/pull/2102

conjure-lib/build.gradle

@@ -26,6 +26,7 @@ dependencies {
 
     implementation 'com.fasterxml.jackson.core:jackson-annotations'
     implementation 'com.fasterxml.jackson.core:jackson-core'
+    implementation 'com.google.guava:guava'
     implementation 'com.palantir.safe-logging:safe-logging'
 
     testImplementation 'com.palantir.safe-logging:preconditions-assertj'

conjure-lib/src/main/java/com/palantir/conjure/java/lib/Bytes.java

@@ -24,11 +24,14 @@
 import com.fasterxml.jackson.databind.SerializerProvider;
 import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
 import com.fasterxml.jackson.databind.annotation.JsonSerialize;
+import com.google.common.primitives.SignedBytes;
+import com.google.common.primitives.UnsignedBytes;
 import java.io.ByteArrayInputStream;
 import java.io.IOException;
 import java.io.InputStream;
 import java.nio.ByteBuffer;
 import java.util.Arrays;
+import java.util.Comparator;
 
 /** An immutable {@code byte[]} wrapper. */
 @JsonSerialize(using = Bytes.Serializer.class)
@@ -114,6 +117,14 @@ public static Bytes from(ByteBuffer buffer) {
         return new Bytes(safe);
     }
 
+    public static Comparator<Bytes> signed() {
+        return (x, y) -> SignedBytes.lexicographicalComparator().compare(x.safe, y.safe);
+    }
+
+    public static Comparator<Bytes> unsigned() {
+        return (x, y) -> UnsignedBytes.lexicographicalComparator().compare(x.safe, y.safe);
+    }
+
     static final class Serializer extends JsonSerializer<Bytes> {
         @Override
         public void serialize(Bytes value, JsonGenerator gen, SerializerProvider _serializer) throws IOException {

conjure-lib/src/test/java/com/palantir/conjure/java/lib/BytesTests.java

@@ -24,6 +24,7 @@
 import java.io.IOException;
 import java.nio.ByteBuffer;
 import java.nio.charset.StandardCharsets;
+import java.util.Comparator;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.parallel.Execution;
 import org.junit.jupiter.api.parallel.ExecutionMode;
@@ -181,4 +182,29 @@ public void testSerDe_cannotMapEmptyArray() {
         ObjectMapper mapper = new ObjectMapper();
         assertThatThrownBy(() -> mapper.readValue("[]", Bytes.class)).isInstanceOf(JsonParseException.class);
     }
+
+    @Test
+    public void testUnsignedComparator() {
+        Comparator<Bytes> comparator = Bytes.unsigned();
+        assertThat(Bytes.from(new byte[] {1})).usingComparator(comparator).isEqualTo(Bytes.from(new byte[] {1}));
+        assertThat(Bytes.from(new byte[] {-1})).usingComparator(comparator).isEqualTo(Bytes.from(new byte[] {-1}));
+        checkComparator(comparator, Bytes.from(new byte[] {-1, 0, 1}), Bytes.from(new byte[] {-1, 0, 2}));
+        checkComparator(comparator, Bytes.from(new byte[] {1, 0, 1}), Bytes.from(new byte[] {-1, 0, 1}));
+    }
+
+    @Test
+    public void testSignedComparator() {
+        Comparator<Bytes> comparator = Bytes.signed();
+        assertThat(Bytes.from(new byte[] {1})).usingComparator(comparator).isEqualTo(Bytes.from(new byte[] {1}));
+        assertThat(Bytes.from(new byte[] {-1})).usingComparator(comparator).isEqualTo(Bytes.from(new byte[] {-1}));
+        checkComparator(comparator, Bytes.from(new byte[] {-1, 0, 1}), Bytes.from(new byte[] {-1, 0, 2}));
+        checkComparator(comparator, Bytes.from(new byte[] {-1, 0, 1}), Bytes.from(new byte[] {1, 0, 1}));
+    }
+
+    private static void checkComparator(Comparator<Bytes> comparator, Bytes lesser, Bytes greater) {
+        assertThat(comparator.compare(lesser, lesser)).isZero();
+        assertThat(comparator.compare(lesser, greater)).isLessThan(0);
+        assertThat(comparator.compare(greater, lesser)).isGreaterThan(0);
+        assertThat(comparator.compare(greater, greater)).isZero();
+    }
 }