feat(key): #773 Expose methods to check if a Key can be parsed

key/src/main/java/net/kyori/adventure/key/Key.java

@@ -29,6 +29,8 @@
 import net.kyori.examination.ExaminableProperty;
 import org.intellij.lang.annotations.Pattern;
 import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+import org.jetbrains.annotations.VisibleForTesting;
 
 /**
  * An identifying object used to fetch and/or store unique objects.
@@ -62,6 +64,12 @@ public interface Key extends Comparable<Key>, Examinable, Namespaced {
    * @since 4.0.0
    */
   String MINECRAFT_NAMESPACE = "minecraft";
+  /**
+   * The default namespace and value separator.
+   *
+   * @since 4.12.0
+   */
+  char DEFAULT_SEPARATOR = ':';
 
   /**
    * Creates a key.
@@ -78,7 +86,7 @@ public interface Key extends Comparable<Key>, Examinable, Namespaced {
    * @since 4.0.0
    */
   static @NotNull Key key(final @NotNull @Pattern("(" + KeyImpl.NAMESPACE_PATTERN + ":)?" + KeyImpl.VALUE_PATTERN) String string) {
-    return key(string, ':');
+    return key(string, DEFAULT_SEPARATOR);
   }
 
   /**
@@ -142,6 +150,79 @@ public interface Key extends Comparable<Key>, Examinable, Namespaced {
     return KeyImpl.COMPARATOR;
   }
 
+  /**
+   * Checks if {@code string} can be parsed into a {@link Key}.
+   *
+   * @param string the input string
+   * @return {@code true} if {@code string} can be parsed into a {@link Key}, {@code false} otherwise
+   * @since 4.12.0
+   */
+  static boolean parseable(final @Nullable String string) {
+    if (string == null) {
+      return false;
+    }
+    final int index = string.indexOf(DEFAULT_SEPARATOR);
+    final String namespace = index >= 1 ? string.substring(0, index) : MINECRAFT_NAMESPACE;
+    final String value = index >= 0 ? string.substring(index + 1) : string;
+    return parseableNamespace(namespace) && parseableValue(value);
+  }
+
+  /**
+   * Checks if {@code value} is a valid namespace.
+   *
+   * @param namespace the string to check
+   * @return {@code true} if {@code value} is a valid namespace, {@code false} otherwise
+   * @since 4.12.0
+   */
+  @VisibleForTesting
+  static boolean parseableNamespace(final @NotNull String namespace) {
+    for (int i = 0, length = namespace.length(); i < length; i++) {
+      if (!allowedInNamespace(namespace.charAt(i))) {
+        return false;
+      }
+    }
+    return true;
+  }
+
+  /**
+   * Checks if {@code value} is a valid value.
+   *
+   * @param value the string to check
+   * @return {@code true} if {@code value} is a valid value, {@code false} otherwise
+   * @since 4.12.0
+   */
+  @VisibleForTesting
+  static boolean parseableValue(final @NotNull String value) {
+    for (int i = 0, length = value.length(); i < length; i++) {
+      if (!allowedInValue(value.charAt(i))) {
+        return false;
+      }
+    }
+    return true;
+  }
+
+  /**
+   * Checks if {@code value} is a valid character in a namespace.
+   *
+   * @param character the character to check
+   * @return {@code true} if {@code value} is a valid character in a namespace, {@code false} otherwise
+   * @since 4.12.0
+   */
+  static boolean allowedInNamespace(final char character) {
+    return KeyImpl.allowedInNamespace(character);
+  }
+
+  /**
+   * Checks if {@code value} is a valid character in a value.
+   *
+   * @param character the character to check
+   * @return {@code true} if {@code value} is a valid character in a value, {@code false} otherwise
+   * @since 4.12.0
+   */
+  static boolean allowedInValue(final char character) {
+    return KeyImpl.allowedInValue(character);
+  }
+
   /**
    * Gets the namespace.
    *

key/src/main/java/net/kyori/adventure/key/KeyImpl.java

@@ -28,7 +28,6 @@
 import java.util.stream.Stream;
 import net.kyori.examination.ExaminableProperty;
 import org.jetbrains.annotations.NotNull;
-import org.jetbrains.annotations.VisibleForTesting;
 
 import static java.util.Objects.requireNonNull;
 
@@ -42,38 +41,18 @@ final class KeyImpl implements Key {
   private final String value;
 
   KeyImpl(final @NotNull String namespace, final @NotNull String value) {
-    if (!namespaceValid(namespace)) throw new InvalidKeyException(namespace, value, String.format("Non [a-z0-9_.-] character in namespace of Key[%s]", asString(namespace, value)));
-    if (!valueValid(value)) throw new InvalidKeyException(namespace, value, String.format("Non [a-z0-9/._-] character in value of Key[%s]", asString(namespace, value)));
+    if (!Key.parseableNamespace(namespace)) throw new InvalidKeyException(namespace, value, String.format("Non [a-z0-9_.-] character in namespace of Key[%s]", asString(namespace, value)));
+    if (!Key.parseableValue(value)) throw new InvalidKeyException(namespace, value, String.format("Non [a-z0-9/._-] character in value of Key[%s]", asString(namespace, value)));
     this.namespace = requireNonNull(namespace, "namespace");
     this.value = requireNonNull(value, "value");
   }
 
-  @VisibleForTesting
-  static boolean namespaceValid(final @NotNull String namespace) {
-    for (int i = 0, length = namespace.length(); i < length; i++) {
-      if (!validNamespaceChar(namespace.charAt(i))) {
-        return false;
-      }
-    }
-    return true;
+  static boolean allowedInNamespace(final char character) {
+    return character == '_' || character == '-' || (character >= 'a' && character <= 'z') || (character >= '0' && character <= '9') || character == '.';
   }
 
-  @VisibleForTesting
-  static boolean valueValid(final @NotNull String value) {
-    for (int i = 0, length = value.length(); i < length; i++) {
-      if (!validValueChar(value.charAt(i))) {
-        return false;
-      }
-    }
-    return true;
-  }
-
-  private static boolean validNamespaceChar(final int value) {
-    return value == '_' || value == '-' || (value >= 'a' && value <= 'z') || (value >= '0' && value <= '9') || value == '.';
-  }
-
-  private static boolean validValueChar(final int value) {
-    return value == '_' || value == '-' || (value >= 'a' && value <= 'z') || (value >= '0' && value <= '9') || value == '/' || value == '.';
+  static boolean allowedInValue(final char character) {
+    return character == '_' || character == '-' || (character >= 'a' && character <= 'z') || (character >= '0' && character <= '9') || character == '.' || character == '/';
   }
 
   @Override

key/src/test/java/net/kyori/adventure/key/KeyTest.java

@@ -90,15 +90,21 @@ void testCompare() {
   }
 
   @Test
-  void testNamespaceValid() {
-    assertTrue(KeyImpl.namespaceValid(Key.MINECRAFT_NAMESPACE));
-    assertTrue(KeyImpl.namespaceValid("realms"));
-    assertFalse(KeyImpl.namespaceValid("some/path"));
+  void testParseable() {
+    assertTrue(Key.parseable("minecraft:empty"));
+    assertFalse(Key.parseable("minecraft:Empty"));
   }
 
   @Test
-  void testValueValid() {
-    assertTrue(KeyImpl.valueValid("empty"));
-    assertTrue(KeyImpl.valueValid("some/path"));
+  void testParseableNamespace() {
+    assertTrue(Key.parseableNamespace(Key.MINECRAFT_NAMESPACE));
+    assertTrue(Key.parseableNamespace("realms"));
+    assertFalse(Key.parseableNamespace("some/path"));
+  }
+
+  @Test
+  void testParseableValue() {
+    assertTrue(Key.parseableValue("empty"));
+    assertTrue(Key.parseableValue("some/path"));
   }
 }