Simplify

jib-core/src/main/java/com/google/cloud/tools/jib/configuration/DockerHealthCheck.java

@@ -30,13 +30,13 @@ public class DockerHealthCheck {
   /** Builds the immutable {@link DockerHealthCheck}. */
   public static class Builder {
 
-    @Nullable private final ImmutableList<String> command;
+    private final ImmutableList<String> command;
     @Nullable private Duration interval;
     @Nullable private Duration timeout;
     @Nullable private Duration startPeriod;
     @Nullable private Integer retries;
 
-    private Builder(@Nullable ImmutableList<String> command) {
+    private Builder(ImmutableList<String> command) {
       this.command = command;
     }
 
@@ -106,7 +106,7 @@ public static DockerHealthCheck disabled() {
    * @return the new {@link DockerHealthCheck}
    */
   public static DockerHealthCheck inherited() {
-    return new DockerHealthCheck(null, null, null, null, null);
+    return new DockerHealthCheck(ImmutableList.of(), null, null, null, null);
   }
 
   /**
@@ -147,14 +147,14 @@ public static Builder builderWithShellCommand(String command) {
     return new Builder(ImmutableList.of("CMD-SHELL", command));
   }
 
-  @Nullable private final ImmutableList<String> command;
+  private final ImmutableList<String> command;
   @Nullable private final Duration interval;
   @Nullable private final Duration timeout;
   @Nullable private final Duration startPeriod;
   @Nullable private final Integer retries;
 
   private DockerHealthCheck(
-      @Nullable ImmutableList<String> command,
+      ImmutableList<String> command,
       @Nullable Duration interval,
       @Nullable Duration timeout,
       @Nullable Duration startPeriod,
@@ -172,8 +172,8 @@ private DockerHealthCheck(
    *
    * @return the healthcheck command
    */
-  public Optional<List<String>> getCommand() {
-    return Optional.ofNullable(command);
+  public List<String> getCommand() {
+    return command;
   }
 
   /**
@@ -222,6 +222,6 @@ public Optional<Integer> getRetries() {
    * @return {@code true} if the health check should be inherited, {@code false} if not
    */
   public boolean isInherited() {
-    return command == null || command.isEmpty();
+    return command.isEmpty();
   }
 }

jib-core/src/main/java/com/google/cloud/tools/jib/image/Image.java

@@ -47,7 +47,7 @@ public static class Builder<T extends Layer> {
     @Nullable private Instant created;
     @Nullable private ImmutableList<String> entrypoint;
     @Nullable private ImmutableList<String> programArguments;
-    private DockerHealthCheck healthCheck = DockerHealthCheck.disabled();
+    private DockerHealthCheck healthCheck = DockerHealthCheck.inherited();
     @Nullable private ImmutableList<Port> exposedPorts;
     @Nullable private ImmutableList<AbsoluteUnixPath> volumes;
     @Nullable private String workingDirectory;

jib-core/src/main/java/com/google/cloud/tools/jib/image/json/ImageToJsonTranslator.java

@@ -172,7 +172,7 @@ public Blob getContainerConfigurationBlob() {
     // Healthcheck is not supported by OCI
     DockerHealthCheck healthCheck = image.getHealthCheck();
     if (image.getImageFormat() == V22ManifestTemplate.class) {
-      template.setContainerHealthTest(healthCheck.getCommand().orElse(ImmutableList.of()));
+      template.setContainerHealthTest(healthCheck.getCommand());
       healthCheck
           .getInterval()
           .ifPresent(interval -> template.setContainerHealthInterval(interval.toNanos()));

jib-core/src/test/java/com/google/cloud/tools/jib/configuration/DockerHealthCheckTest.java

@@ -47,39 +47,33 @@ public void testBuild_parameters() {
   @Test
   public void testBuild_propagated() {
     DockerHealthCheck healthCheck = DockerHealthCheck.inherited();
-    Assert.assertFalse(healthCheck.getCommand().isPresent());
     Assert.assertTrue(healthCheck.isInherited());
   }
 
   @Test
   public void testBuild_execArray() {
     DockerHealthCheck healthCheck =
         DockerHealthCheck.builderWithExecCommand("test", "command").build();
-    Assert.assertTrue(healthCheck.getCommand().isPresent());
-    Assert.assertEquals(ImmutableList.of("CMD", "test", "command"), healthCheck.getCommand().get());
+    Assert.assertEquals(ImmutableList.of("CMD", "test", "command"), healthCheck.getCommand());
   }
 
   @Test
   public void testBuild_execList() {
     DockerHealthCheck healthCheck =
         DockerHealthCheck.builderWithExecCommand(ImmutableList.of("test", "command")).build();
-    Assert.assertTrue(healthCheck.getCommand().isPresent());
-    Assert.assertEquals(ImmutableList.of("CMD", "test", "command"), healthCheck.getCommand().get());
+    Assert.assertEquals(ImmutableList.of("CMD", "test", "command"), healthCheck.getCommand());
   }
 
   @Test
   public void testBuild_shell() {
     DockerHealthCheck healthCheck =
         DockerHealthCheck.builderWithShellCommand("shell command").build();
-    Assert.assertTrue(healthCheck.getCommand().isPresent());
-    Assert.assertEquals(
-        ImmutableList.of("CMD-SHELL", "shell command"), healthCheck.getCommand().get());
+    Assert.assertEquals(ImmutableList.of("CMD-SHELL", "shell command"), healthCheck.getCommand());
   }
 
   @Test
   public void testDisabled() {
     DockerHealthCheck healthCheck = DockerHealthCheck.disabled();
-    Assert.assertTrue(healthCheck.getCommand().isPresent());
-    Assert.assertEquals(ImmutableList.of("NONE"), healthCheck.getCommand().get());
+    Assert.assertEquals(ImmutableList.of("NONE"), healthCheck.getCommand());
   }
 }