Refactor the API for v1 (#226)

It's a bit ugly but seems like our best option since Java doesn't have
any concept of `internal` packages. This mirrors the Go protovalidate
package structure changes we did in
bufbuild/protovalidate-go#173.

The primary goal of this PR is to reduce the surface area of incidental
public API. We don't want to expose our internal logic since it is very
likely to be refactored in incompatible ways, but many things in the
`internal` package are currently publicly accessible.

src/main/java/build/buf/protovalidate/internal/evaluator/AnyEvaluator.java → src/main/java/build/buf/protovalidate/AnyEvaluator.java

@@ -12,11 +12,9 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package build.buf.protovalidate.internal.evaluator;
+package build.buf.protovalidate;
 
 import build.buf.protovalidate.exceptions.ExecutionException;
-import build.buf.protovalidate.internal.errors.ConstraintViolation;
-import build.buf.protovalidate.internal.errors.FieldPathUtils;
 import build.buf.validate.AnyRules;
 import build.buf.validate.FieldConstraints;
 import build.buf.validate.FieldPath;

src/main/java/build/buf/protovalidate/internal/expression/AstExpression.java → src/main/java/build/buf/protovalidate/AstExpression.java

@@ -12,15 +12,15 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package build.buf.protovalidate.internal.expression;
+package build.buf.protovalidate;
 
 import build.buf.protovalidate.exceptions.CompilationException;
 import com.google.api.expr.v1alpha1.Type;
 import org.projectnessie.cel.Ast;
 import org.projectnessie.cel.Env;
 
 /** {@link AstExpression} is a compiled CEL {@link Ast}. */
-public class AstExpression {
+class AstExpression {
   /** The compiled CEL AST. */
   public final Ast ast;
 

src/main/java/build/buf/protovalidate/internal/evaluator/CelPrograms.java → src/main/java/build/buf/protovalidate/CelPrograms.java

@@ -12,13 +12,9 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package build.buf.protovalidate.internal.evaluator;
+package build.buf.protovalidate;
 
 import build.buf.protovalidate.exceptions.ExecutionException;
-import build.buf.protovalidate.internal.errors.ConstraintViolation;
-import build.buf.protovalidate.internal.errors.FieldPathUtils;
-import build.buf.protovalidate.internal.expression.CompiledProgram;
-import build.buf.protovalidate.internal.expression.Variable;
 import java.util.ArrayList;
 import java.util.List;
 import javax.annotation.Nullable;

src/main/java/build/buf/protovalidate/internal/expression/CompiledProgram.java → src/main/java/build/buf/protovalidate/CompiledProgram.java

@@ -12,11 +12,9 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package build.buf.protovalidate.internal.expression;
+package build.buf.protovalidate;
 
 import build.buf.protovalidate.exceptions.ExecutionException;
-import build.buf.protovalidate.internal.errors.ConstraintViolation;
-import build.buf.protovalidate.internal.evaluator.Value;
 import build.buf.validate.FieldPath;
 import javax.annotation.Nullable;
 import org.projectnessie.cel.Program;
@@ -27,7 +25,7 @@
  * {@link CompiledProgram} is a parsed and type-checked {@link Program} along with the source {@link
  * Expression}.
  */
-public class CompiledProgram {
+class CompiledProgram {
   /** A compiled CEL program that can be evaluated against a set of variable bindings. */
   private final Program program;
 

src/main/java/build/buf/protovalidate/internal/constraints/ConstraintCache.java → src/main/java/build/buf/protovalidate/ConstraintCache.java

@@ -12,17 +12,9 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package build.buf.protovalidate.internal.constraints;
+package build.buf.protovalidate;
 
-import build.buf.protovalidate.Config;
 import build.buf.protovalidate.exceptions.CompilationException;
-import build.buf.protovalidate.internal.errors.FieldPathUtils;
-import build.buf.protovalidate.internal.evaluator.ObjectValue;
-import build.buf.protovalidate.internal.evaluator.Value;
-import build.buf.protovalidate.internal.expression.AstExpression;
-import build.buf.protovalidate.internal.expression.CompiledProgram;
-import build.buf.protovalidate.internal.expression.Expression;
-import build.buf.protovalidate.internal.expression.Variable;
 import build.buf.validate.FieldConstraints;
 import build.buf.validate.FieldPath;
 import build.buf.validate.ValidateProto;
@@ -52,7 +44,7 @@
 import org.projectnessie.cel.interpreter.Activation;
 
 /** A build-through cache for computed standard constraints. */
-public class ConstraintCache {
+class ConstraintCache {
   private static class CelRule {
     public final AstExpression astExpression;
     public final FieldDescriptor field;

src/main/java/build/buf/protovalidate/internal/evaluator/ConstraintResolver.java → src/main/java/build/buf/protovalidate/ConstraintResolver.java

@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package build.buf.protovalidate.internal.evaluator;
+package build.buf.protovalidate;
 
 import build.buf.protovalidate.exceptions.CompilationException;
 import build.buf.validate.FieldConstraints;

src/main/java/build/buf/protovalidate/internal/errors/ConstraintViolation.java → src/main/java/build/buf/protovalidate/ConstraintViolation.java

@@ -12,10 +12,8 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package build.buf.protovalidate.internal.errors;
+package build.buf.protovalidate;
 
-import build.buf.protovalidate.Violation;
-import build.buf.protovalidate.internal.evaluator.Value;
 import build.buf.validate.FieldPath;
 import build.buf.validate.FieldPathElement;
 import com.google.protobuf.Descriptors;
@@ -31,7 +29,7 @@
  * {@link ConstraintViolation} contains all of the collected information about an individual
  * constraint violation.
  */
-public class ConstraintViolation implements Violation {
+class ConstraintViolation implements Violation {
   /** Static value to return when there are no violations. */
   public static final List<Builder> NO_VIOLATIONS = new ArrayList<>();
 

src/main/java/build/buf/protovalidate/internal/evaluator/ConstraintViolationHelper.java → src/main/java/build/buf/protovalidate/ConstraintViolationHelper.java

@@ -12,9 +12,8 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package build.buf.protovalidate.internal.evaluator;
+package build.buf.protovalidate;
 
-import build.buf.protovalidate.internal.errors.FieldPathUtils;
 import build.buf.validate.FieldPath;
 import build.buf.validate.FieldPathElement;
 import java.util.ArrayList;

src/main/java/build/buf/protovalidate/internal/celext/CustomDeclarations.java → src/main/java/build/buf/protovalidate/CustomDeclarations.java

@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package build.buf.protovalidate.internal.celext;
+package build.buf.protovalidate;
 
 import com.google.api.expr.v1alpha1.Decl;
 import java.util.ArrayList;

src/main/java/build/buf/protovalidate/internal/celext/CustomOverload.java → src/main/java/build/buf/protovalidate/CustomOverload.java

@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package build.buf.protovalidate.internal.celext;
+package build.buf.protovalidate;
 
 import com.google.common.base.Ascii;
 import com.google.common.base.Splitter;

src/main/java/build/buf/protovalidate/internal/constraints/DescriptorMappings.java → src/main/java/build/buf/protovalidate/DescriptorMappings.java

@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package build.buf.protovalidate.internal.constraints;
+package build.buf.protovalidate;
 
 import build.buf.validate.FieldConstraints;
 import com.google.api.expr.v1alpha1.Type;
@@ -27,7 +27,7 @@
 /**
  * DescriptorMappings provides mappings between protocol buffer descriptors and CEL declarations.
  */
-public final class DescriptorMappings {
+final class DescriptorMappings {
   /** Provides a {@link Descriptor} for {@link FieldConstraints}. */
   static final Descriptor FIELD_CONSTRAINTS_DESC = FieldConstraints.getDescriptor();
 

src/main/java/build/buf/protovalidate/internal/evaluator/EmbeddedMessageEvaluator.java → src/main/java/build/buf/protovalidate/EmbeddedMessageEvaluator.java

@@ -12,11 +12,9 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package build.buf.protovalidate.internal.evaluator;
+package build.buf.protovalidate;
 
 import build.buf.protovalidate.exceptions.ExecutionException;
-import build.buf.protovalidate.internal.errors.ConstraintViolation;
-import build.buf.protovalidate.internal.errors.FieldPathUtils;
 import java.util.Collections;
 import java.util.List;
 

src/main/java/build/buf/protovalidate/internal/evaluator/EnumEvaluator.java → src/main/java/build/buf/protovalidate/EnumEvaluator.java

@@ -12,12 +12,9 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package build.buf.protovalidate.internal.evaluator;
+package build.buf.protovalidate;
 
-import build.buf.protovalidate.ValidationResult;
 import build.buf.protovalidate.exceptions.ExecutionException;
-import build.buf.protovalidate.internal.errors.ConstraintViolation;
-import build.buf.protovalidate.internal.errors.FieldPathUtils;
 import build.buf.validate.EnumRules;
 import build.buf.validate.FieldConstraints;
 import build.buf.validate.FieldPath;

src/main/java/build/buf/protovalidate/internal/evaluator/Evaluator.java → src/main/java/build/buf/protovalidate/Evaluator.java

@@ -12,17 +12,16 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package build.buf.protovalidate.internal.evaluator;
+package build.buf.protovalidate;
 
 import build.buf.protovalidate.exceptions.ExecutionException;
-import build.buf.protovalidate.internal.errors.ConstraintViolation;
 import java.util.List;
 
 /**
  * {@link Evaluator} defines a validation evaluator. evaluator implementations may elide type
  * checking of the passed in value, as the types have been guaranteed during the build phase.
  */
-public interface Evaluator {
+interface Evaluator {
   /**
    * Tautology returns true if the evaluator always succeeds.
    *

src/main/java/build/buf/protovalidate/internal/evaluator/EvaluatorBuilder.java → src/main/java/build/buf/protovalidate/EvaluatorBuilder.java

@@ -12,17 +12,9 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package build.buf.protovalidate.internal.evaluator;
+package build.buf.protovalidate;
 
-import build.buf.protovalidate.Config;
 import build.buf.protovalidate.exceptions.CompilationException;
-import build.buf.protovalidate.internal.constraints.ConstraintCache;
-import build.buf.protovalidate.internal.constraints.DescriptorMappings;
-import build.buf.protovalidate.internal.errors.FieldPathUtils;
-import build.buf.protovalidate.internal.expression.AstExpression;
-import build.buf.protovalidate.internal.expression.CompiledProgram;
-import build.buf.protovalidate.internal.expression.Expression;
-import build.buf.protovalidate.internal.expression.Variable;
 import build.buf.validate.Constraint;
 import build.buf.validate.FieldConstraints;
 import build.buf.validate.FieldPath;
@@ -50,7 +42,7 @@
 import org.projectnessie.cel.checker.Decls;
 
 /** A build-through cache of message evaluators keyed off the provided descriptor. */
-public class EvaluatorBuilder {
+class EvaluatorBuilder {
   private static final FieldPathElement CEL_FIELD_PATH_ELEMENT =
       FieldPathUtils.fieldPathElement(
           FieldConstraints.getDescriptor().findFieldByNumber(FieldConstraints.CEL_FIELD_NUMBER));

src/main/java/build/buf/protovalidate/internal/expression/Expression.java → src/main/java/build/buf/protovalidate/Expression.java

@@ -12,14 +12,14 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package build.buf.protovalidate.internal.expression;
+package build.buf.protovalidate;
 
 import build.buf.validate.Constraint;
 import java.util.ArrayList;
 import java.util.List;
 
 /** Expression represents a single CEL expression. */
-public class Expression {
+class Expression {
   /** The id of the constraint. */
   public final String id;
 

src/main/java/build/buf/protovalidate/internal/evaluator/FieldEvaluator.java → src/main/java/build/buf/protovalidate/FieldEvaluator.java

@@ -12,11 +12,9 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package build.buf.protovalidate.internal.evaluator;
+package build.buf.protovalidate;
 
 import build.buf.protovalidate.exceptions.ExecutionException;
-import build.buf.protovalidate.internal.errors.ConstraintViolation;
-import build.buf.protovalidate.internal.errors.FieldPathUtils;
 import build.buf.validate.FieldConstraints;
 import build.buf.validate.FieldPath;
 import com.google.protobuf.Descriptors.FieldDescriptor;

src/main/java/build/buf/protovalidate/internal/errors/FieldPathUtils.java → src/main/java/build/buf/protovalidate/FieldPathUtils.java

@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package build.buf.protovalidate.internal.errors;
+package build.buf.protovalidate;
 
 import build.buf.validate.FieldPath;
 import build.buf.validate.FieldPathElement;
@@ -21,7 +21,7 @@
 import javax.annotation.Nullable;
 
 /** Utility class for manipulating error paths in violations. */
-public final class FieldPathUtils {
+final class FieldPathUtils {
   private FieldPathUtils() {}
 
   /**

src/main/java/build/buf/protovalidate/internal/celext/Format.java → src/main/java/build/buf/protovalidate/Format.java

@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package build.buf.protovalidate.internal.celext;
+package build.buf.protovalidate;
 
 import static java.time.format.DateTimeFormatter.ISO_INSTANT;
 

src/main/java/build/buf/protovalidate/internal/evaluator/ListEvaluator.java → src/main/java/build/buf/protovalidate/ListEvaluator.java

@@ -12,11 +12,9 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package build.buf.protovalidate.internal.evaluator;
+package build.buf.protovalidate;
 
 import build.buf.protovalidate.exceptions.ExecutionException;
-import build.buf.protovalidate.internal.errors.ConstraintViolation;
-import build.buf.protovalidate.internal.errors.FieldPathUtils;
 import build.buf.validate.FieldConstraints;
 import build.buf.validate.FieldPath;
 import build.buf.validate.FieldPathElement;

src/main/java/build/buf/protovalidate/internal/evaluator/MapEvaluator.java → src/main/java/build/buf/protovalidate/MapEvaluator.java

@@ -12,11 +12,9 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package build.buf.protovalidate.internal.evaluator;
+package build.buf.protovalidate;
 
 import build.buf.protovalidate.exceptions.ExecutionException;
-import build.buf.protovalidate.internal.errors.ConstraintViolation;
-import build.buf.protovalidate.internal.errors.FieldPathUtils;
 import build.buf.validate.FieldConstraints;
 import build.buf.validate.FieldPath;
 import build.buf.validate.FieldPathElement;

src/main/java/build/buf/protovalidate/internal/evaluator/MessageEvaluator.java → src/main/java/build/buf/protovalidate/MessageEvaluator.java

@@ -12,10 +12,9 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package build.buf.protovalidate.internal.evaluator;
+package build.buf.protovalidate;
 
 import build.buf.protovalidate.exceptions.ExecutionException;
-import build.buf.protovalidate.internal.errors.ConstraintViolation;
 import java.util.ArrayList;
 import java.util.List;
 

src/main/java/build/buf/protovalidate/internal/evaluator/MessageValue.java → src/main/java/build/buf/protovalidate/MessageValue.java

@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package build.buf.protovalidate.internal.evaluator;
+package build.buf.protovalidate;
 
 import com.google.protobuf.Descriptors;
 import com.google.protobuf.Message;
@@ -21,11 +21,8 @@
 import java.util.Map;
 import javax.annotation.Nullable;
 
-/**
- * The {@link build.buf.protovalidate.internal.evaluator.Value} type that contains a {@link
- * com.google.protobuf.Message}.
- */
-public final class MessageValue implements Value {
+/** The {@link Value} type that contains a {@link com.google.protobuf.Message}. */
+final class MessageValue implements Value {
 
   /** Object type since the object type is inferred from the field descriptor. */
   private final Object value;

src/main/java/build/buf/protovalidate/internal/expression/NowVariable.java → src/main/java/build/buf/protovalidate/NowVariable.java

@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package build.buf.protovalidate.internal.expression;
+package build.buf.protovalidate;
 
 import java.time.Instant;
 import javax.annotation.Nullable;
@@ -24,7 +24,7 @@
  * {@link NowVariable} implements {@link Activation}, providing a lazily produced timestamp for
  * accessing the variable `now` that's constant within an evaluation.
  */
-public class NowVariable implements Activation {
+class NowVariable implements Activation {
   /** The name of the 'now' variable. */
   private static final String NOW_NAME = "now";