* characters.
 *
 * <p>As there are important reasons, including potential security issues, to handle Unicode
 * correctly if you are considering implementing a new escaper you should favor using UnicodeEscaper
 * wherever possible.
 *
 * <p>A {@code UnicodeEscaper} instance is required to be stateless, and safe when used concurrently
 * by multiple threads.
 *
 * <p>Popular escapers are defined as constants in classes like {@link

  // Escapes nothing
  private static final UnicodeEscaper NOP_ESCAPER =
      new UnicodeEscaper() {
        @Override
        protected char @Nullable [] escape(int c) {
          return null;
        }
      };

  // Escapes everything except [a-zA-Z0-9]
  private static final UnicodeEscaper SIMPLE_ESCAPER =
      new UnicodeEscaper() {
        @Override
        protected char @Nullable [] escape(int cp) {

  // Escapes nothing
  private static final UnicodeEscaper NOP_ESCAPER =
      new UnicodeEscaper() {
        @Override
        protected char @Nullable [] escape(int c) {
          return null;
        }
      };

  // Escapes everything except [a-zA-Z0-9]
  private static final UnicodeEscaper SIMPLE_ESCAPER =
      new UnicodeEscaper() {
        @Override
        protected char @Nullable [] escape(int cp) {

                .put('\uDC00', "<lo>".toCharArray())
                .buildOrThrow());
    UnicodeEscaper unicodeEscaper = Escapers.asUnicodeEscaper(charEscaper);
    EscaperAsserts.assertBasic(unicodeEscaper);
    assertEquals("<hello><hi><lo>", charEscaper.escape("x\uD800\uDC00"));
    assertEquals("<hello><hi><lo>", unicodeEscaper.escape("x\uD800\uDC00"));

    // Test that wrapped escapers acquire good Unicode semantics.

import com.google.common.annotations.GwtCompatible;
import com.google.common.escape.CharEscaper;
import com.google.common.escape.Escaper;
import com.google.common.escape.UnicodeEscaper;
import java.io.IOException;
import junit.framework.Assert;

/**
 * Extra assert methods for testing Escaper implementations.
 *
 * @author David Beaumont
 * @since 15.0
 */
@GwtCompatible

  }

  /** Tests the various ways that the space character can be handled */
  public void testPlusForSpace() {
    UnicodeEscaper basicEscaper = new PercentEscaper("", false);
    UnicodeEscaper plusForSpaceEscaper = new PercentEscaper("", true);
    UnicodeEscaper spaceEscaper = new PercentEscaper(" ", false);

    assertEquals("string%20with%20spaces", basicEscaper.escape("string with spaces"));

                .put('\uDC00', "<lo>".toCharArray())
                .buildOrThrow());
    UnicodeEscaper unicodeEscaper = Escapers.asUnicodeEscaper(charEscaper);
    EscaperAsserts.assertBasic(unicodeEscaper);
    assertEquals("<hello><hi><lo>", charEscaper.escape("x\uD800\uDC00"));
    assertEquals("<hello><hi><lo>", unicodeEscaper.escape("x\uD800\uDC00"));

    // Test that wrapped escapers acquire good Unicode semantics.

import com.google.common.annotations.GwtCompatible;
import java.util.Map;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * A {@link UnicodeEscaper} that uses an array to quickly look up replacement characters for a given
 * code point. An additional safe range is provided that determines whether code points without

  }

  /** Tests the various ways that the space character can be handled */
  public void testPlusForSpace() {
    UnicodeEscaper basicEscaper = new PercentEscaper("", false);
    UnicodeEscaper plusForSpaceEscaper = new PercentEscaper("", true);
    UnicodeEscaper spaceEscaper = new PercentEscaper(" ", false);

    assertEquals("string%20with%20spaces", basicEscaper.escape("string with spaces"));

import com.google.common.annotations.GwtCompatible;
import com.google.common.escape.CharEscaper;
import com.google.common.escape.Escaper;
import com.google.common.escape.UnicodeEscaper;
import java.io.IOException;
import junit.framework.Assert;

/**
 * Extra assert methods for testing Escaper implementations.
 *
 * @author David Beaumont
 * @since 15.0
 */
@GwtCompatible