diff --git a/spring-core/src/test/java/org/springframework/util/PlaceholderParserTests.java b/spring-core/src/test/java/org/springframework/util/PlaceholderParserTests.java
index 53182acf882..b16f741517a 100644
--- a/spring-core/src/test/java/org/springframework/util/PlaceholderParserTests.java
+++ b/spring-core/src/test/java/org/springframework/util/PlaceholderParserTests.java
@@ -16,7 +16,7 @@
 
 package org.springframework.util;
 
-import java.util.Properties;
+import java.util.Map;
 import java.util.stream.Stream;
 
 import org.junit.jupiter.api.Nested;
@@ -36,13 +36,13 @@ import static org.assertj.core.api.Assertions.assertThatThrownBy;
 import static org.mockito.BDDMockito.given;
 import static org.mockito.Mockito.inOrder;
 import static org.mockito.Mockito.mock;
-import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.verifyNoMoreInteractions;
 
 /**
  * Tests for {@link PlaceholderParser}.
  *
  * @author Stephane Nicoll
+ * @author Sam Brannen
  */
 class PlaceholderParserTests {
 
@@ -54,11 +54,11 @@ class PlaceholderParserTests {
 		@ParameterizedTest(name = "{0} -> {1}")
 		@MethodSource("placeholders")
 		void placeholderIsReplaced(String text, String expected) {
-			Properties properties = new Properties();
-			properties.setProperty("firstName", "John");
-			properties.setProperty("nested0", "first");
-			properties.setProperty("nested1", "Name");
-			assertThat(this.parser.replacePlaceholders(text, properties::getProperty)).isEqualTo(expected);
+			Map<String, String> properties = Map.of(
+					"firstName", "John",
+					"nested0", "first",
+					"nested1", "Name");
+			assertThat(this.parser.replacePlaceholders(text, properties::get)).isEqualTo(expected);
 		}
 
 		static Stream<Arguments> placeholders() {
@@ -79,13 +79,13 @@ class PlaceholderParserTests {
 		@ParameterizedTest(name = "{0} -> {1}")
 		@MethodSource("nestedPlaceholders")
 		void nestedPlaceholdersAreReplaced(String text, String expected) {
-			Properties properties = new Properties();
-			properties.setProperty("p1", "v1");
-			properties.setProperty("p2", "v2");
-			properties.setProperty("p3", "${p1}:${p2}");              // nested placeholders
-			properties.setProperty("p4", "${p3}");                    // deeply nested placeholders
-			properties.setProperty("p5", "${p1}:${p2}:${bogus}");     // unresolvable placeholder
-			assertThat(this.parser.replacePlaceholders(text, properties::getProperty)).isEqualTo(expected);
+			Map<String, String> properties = Map.of(
+					"p1", "v1",
+					"p2", "v2",
+					"p3", "${p1}:${p2}",              // nested placeholders
+					"p4", "${p3}",                    // deeply nested placeholders
+					"p5", "${p1}:${p2}:${bogus}");    // unresolvable placeholder
+			assertThat(this.parser.replacePlaceholders(text, properties::get)).isEqualTo(expected);
 		}
 
 		static Stream<Arguments> nestedPlaceholders() {
@@ -101,19 +101,15 @@ class PlaceholderParserTests {
 		@Test
 		void parseWithSinglePlaceholder() {
 			PlaceholderResolver resolver = mockPlaceholderResolver("firstName", "John");
-			assertThat(this.parser.replacePlaceholders("${firstName}", resolver))
-					.isEqualTo("John");
-			verify(resolver).resolvePlaceholder("firstName");
-			verifyNoMoreInteractions(resolver);
+			assertThat(this.parser.replacePlaceholders("${firstName}", resolver)).isEqualTo("John");
+			verifyPlaceholderResolutions(resolver, "firstName");
 		}
 
 		@Test
 		void parseWithPlaceholderAndPrefixText() {
 			PlaceholderResolver resolver = mockPlaceholderResolver("firstName", "John");
-			assertThat(this.parser.replacePlaceholders("This is ${firstName}", resolver))
-					.isEqualTo("This is John");
-			verify(resolver).resolvePlaceholder("firstName");
-			verifyNoMoreInteractions(resolver);
+			assertThat(this.parser.replacePlaceholders("This is ${firstName}", resolver)).isEqualTo("This is John");
+			verifyPlaceholderResolutions(resolver, "firstName");
 		}
 
 		@Test
@@ -121,31 +117,25 @@ class PlaceholderParserTests {
 			PlaceholderResolver resolver = mockPlaceholderResolver("firstName", "John", "lastName", "Smith");
 			assertThat(this.parser.replacePlaceholders("User: ${firstName} - ${lastName}.", resolver))
 					.isEqualTo("User: John - Smith.");
-			verify(resolver).resolvePlaceholder("firstName");
-			verify(resolver).resolvePlaceholder("lastName");
-			verifyNoMoreInteractions(resolver);
+			verifyPlaceholderResolutions(resolver, "firstName", "lastName");
 		}
 
 		@Test
 		void parseWithNestedPlaceholderInKey() {
-			PlaceholderResolver resolver = mockPlaceholderResolver(
-					"nested", "Name", "firstName", "John");
-			assertThat(this.parser.replacePlaceholders("${first${nested}}", resolver))
-					.isEqualTo("John");
+			PlaceholderResolver resolver = mockPlaceholderResolver("nested", "Name", "firstName", "John");
+			assertThat(this.parser.replacePlaceholders("${first${nested}}", resolver)).isEqualTo("John");
 			verifyPlaceholderResolutions(resolver, "nested", "firstName");
 		}
 
 		@Test
 		void parseWithMultipleNestedPlaceholdersInKey() {
-			PlaceholderResolver resolver = mockPlaceholderResolver(
-					"nested0", "first", "nested1", "Name", "firstName", "John");
-			assertThat(this.parser.replacePlaceholders("${${nested0}${nested1}}", resolver))
-					.isEqualTo("John");
+			PlaceholderResolver resolver = mockPlaceholderResolver("nested0", "first", "nested1", "Name", "firstName", "John");
+			assertThat(this.parser.replacePlaceholders("${${nested0}${nested1}}", resolver)).isEqualTo("John");
 			verifyPlaceholderResolutions(resolver, "nested0", "nested1", "firstName");
 		}
 
 		@Test
-		void placeholdersWithSeparatorAreHandledAsIs() {
+		void placeholderValueContainingSeparatorIsHandledAsIs() {
 			PlaceholderResolver resolver = mockPlaceholderResolver("my:test", "value");
 			assertThat(this.parser.replacePlaceholders("${my:test}", resolver)).isEqualTo("value");
 			verifyPlaceholderResolutions(resolver, "my:test");
@@ -153,17 +143,20 @@ class PlaceholderParserTests {
 
 		@Test
 		void placeholdersWithoutEscapeCharAreNotEscaped() {
-			PlaceholderResolver resolver = mockPlaceholderResolver("test", "value");
-			assertThat(this.parser.replacePlaceholders("\\${test}", resolver)).isEqualTo("\\value");
-			verifyPlaceholderResolutions(resolver, "test");
+			PlaceholderResolver resolver = mockPlaceholderResolver("p1", "v1", "p2", "v2", "p3", "v3", "p4", "v4");
+			assertThat(this.parser.replacePlaceholders("\\${p1}", resolver)).isEqualTo("\\v1");
+			assertThat(this.parser.replacePlaceholders("\\\\${p2}", resolver)).isEqualTo("\\\\v2");
+			assertThat(this.parser.replacePlaceholders("\\${p3}\\", resolver)).isEqualTo("\\v3\\");
+			assertThat(this.parser.replacePlaceholders("a\\${p4}\\z", resolver)).isEqualTo("a\\v4\\z");
+			verifyPlaceholderResolutions(resolver, "p1", "p2", "p3", "p4");
 		}
 
 		@Test
-		void textWithInvalidPlaceholderIsMerged() {
+		void textWithInvalidPlaceholderSyntaxIsMerged() {
 			String text = "test${of${with${and${";
 			ParsedValue parsedValue = this.parser.parse(text);
-			assertThat(parsedValue.parts()).singleElement().isInstanceOfSatisfying(
-					TextPart.class, textPart -> assertThat(textPart.text()).isEqualTo(text));
+			assertThat(parsedValue.parts()).singleElement().isInstanceOfSatisfying(TextPart.class,
+					textPart -> assertThat(textPart.text()).isEqualTo(text));
 		}
 
 	}
@@ -176,11 +169,11 @@ class PlaceholderParserTests {
 		@ParameterizedTest(name = "{0} -> {1}")
 		@MethodSource("placeholders")
 		void placeholderIsReplaced(String text, String expected) {
-			Properties properties = new Properties();
-			properties.setProperty("firstName", "John");
-			properties.setProperty("nested0", "first");
-			properties.setProperty("nested1", "Name");
-			assertThat(this.parser.replacePlaceholders(text, properties::getProperty)).isEqualTo(expected);
+			Map<String, String> properties = Map.of(
+					"firstName", "John",
+					"nested0", "first",
+					"nested1", "Name");
+			assertThat(this.parser.replacePlaceholders(text, properties::get)).isEqualTo(expected);
 		}
 
 		static Stream<Arguments> placeholders() {
@@ -199,14 +192,14 @@ class PlaceholderParserTests {
 		@ParameterizedTest(name = "{0} -> {1}")
 		@MethodSource("nestedPlaceholders")
 		void nestedPlaceholdersAreReplaced(String text, String expected) {
-			Properties properties = new Properties();
-			properties.setProperty("p1", "v1");
-			properties.setProperty("p2", "v2");
-			properties.setProperty("p3", "${p1}:${p2}");              // nested placeholders
-			properties.setProperty("p4", "${p3}");                    // deeply nested placeholders
-			properties.setProperty("p5", "${p1}:${p2}:${bogus}");     // unresolvable placeholder
-			properties.setProperty("p6", "${p1}:${p2}:${bogus:def}"); // unresolvable w/ default
-			assertThat(this.parser.replacePlaceholders(text, properties::getProperty)).isEqualTo(expected);
+			Map<String, String> properties = Map.of(
+					"p1", "v1",
+					"p2", "v2",
+					"p3", "${p1}:${p2}",               // nested placeholders
+					"p4", "${p3}",                     // deeply nested placeholders
+					"p5", "${p1}:${p2}:${bogus}",      // unresolvable placeholder
+					"p6", "${p1}:${p2}:${bogus:def}"); // unresolvable w/ default
+			assertThat(this.parser.replacePlaceholders(text, properties::get)).isEqualTo(expected);
 		}
 
 		static Stream<Arguments> nestedPlaceholders() {
@@ -225,11 +218,11 @@ class PlaceholderParserTests {
 		@ParameterizedTest(name = "{0} -> {1}")
 		@MethodSource("exactMatchPlaceholders")
 		void placeholdersWithExactMatchAreConsidered(String text, String expected) {
-			Properties properties = new Properties();
-			properties.setProperty("prefix://my-service", "example-service");
-			properties.setProperty("px", "prefix");
-			properties.setProperty("p1", "${prefix://my-service}");
-			assertThat(this.parser.replacePlaceholders(text, properties::getProperty)).isEqualTo(expected);
+			Map<String, String> properties = Map.of(
+					"prefix://my-service", "example-service",
+					"px", "prefix",
+					"p1", "${prefix://my-service}");
+			assertThat(this.parser.replacePlaceholders(text, properties::get)).isEqualTo(expected);
 		}
 
 		static Stream<Arguments> exactMatchPlaceholders() {
@@ -242,74 +235,55 @@ class PlaceholderParserTests {
 		@Test
 		void parseWithKeyEqualsToText() {
 			PlaceholderResolver resolver = mockPlaceholderResolver("firstName", "Steve");
-			assertThat(this.parser.replacePlaceholders("${firstName}", resolver))
-					.isEqualTo("Steve");
+			assertThat(this.parser.replacePlaceholders("${firstName}", resolver)).isEqualTo("Steve");
 			verifyPlaceholderResolutions(resolver, "firstName");
 		}
 
 		@Test
 		void parseWithHardcodedFallback() {
 			PlaceholderResolver resolver = mockPlaceholderResolver();
-			assertThat(this.parser.replacePlaceholders("${firstName:Steve}", resolver))
-					.isEqualTo("Steve");
+			assertThat(this.parser.replacePlaceholders("${firstName:Steve}", resolver)).isEqualTo("Steve");
 			verifyPlaceholderResolutions(resolver, "firstName:Steve", "firstName");
 		}
 
 		@Test
 		void parseWithNestedPlaceholderInKeyUsingFallback() {
 			PlaceholderResolver resolver = mockPlaceholderResolver("firstName", "John");
-			assertThat(this.parser.replacePlaceholders("${first${invalid:Name}}", resolver))
-					.isEqualTo("John");
+			assertThat(this.parser.replacePlaceholders("${first${invalid:Name}}", resolver)).isEqualTo("John");
 			verifyPlaceholderResolutions(resolver, "invalid:Name", "invalid", "firstName");
 		}
 
 		@Test
 		void parseWithFallbackUsingPlaceholder() {
 			PlaceholderResolver resolver = mockPlaceholderResolver("firstName", "John");
-			assertThat(this.parser.replacePlaceholders("${invalid:${firstName}}", resolver))
-					.isEqualTo("John");
+			assertThat(this.parser.replacePlaceholders("${invalid:${firstName}}", resolver)).isEqualTo("John");
 			verifyPlaceholderResolutions(resolver, "invalid", "firstName");
 		}
 
 	}
 
-	@Nested // Tests with the use of the escape character
+	/**
+	 * Tests that use the escape character.
+	 */
+	@Nested
 	class EscapedTests {
 
 		private final PlaceholderParser parser = new PlaceholderParser("${", "}", ":", '\\', true);
 
-		@ParameterizedTest(name = "{0} -> {1}")
-		@MethodSource("escapedInNestedPlaceholders")
-		void escapedSeparatorInNestedPlaceholder(String text, String expected) {
-			Properties properties = new Properties();
-			properties.setProperty("app.environment", "qa");
-			properties.setProperty("app.service", "protocol");
-			properties.setProperty("protocol://host/qa/name", "protocol://example.com/qa/name");
-			properties.setProperty("service/host/qa/name", "https://example.com/qa/name");
-			properties.setProperty("service/host/qa/name:value", "https://example.com/qa/name-value");
-			assertThat(this.parser.replacePlaceholders(text, properties::getProperty)).isEqualTo(expected);
-		}
-
-		static Stream<Arguments> escapedInNestedPlaceholders() {
-			return Stream.of(
-					Arguments.of("${protocol\\://host/${app.environment}/name}", "protocol://example.com/qa/name"),
-					Arguments.of("${${app.service}\\://host/${app.environment}/name}", "protocol://example.com/qa/name"),
-					Arguments.of("${service/host/${app.environment}/name:\\value}", "https://example.com/qa/name"),
-					Arguments.of("${service/host/${name\\:value}/}", "${service/host/${name:value}/}"));
-		}
-
 		@ParameterizedTest(name = "{0} -> {1}")
 		@MethodSource("escapedPlaceholders")
 		void escapedPlaceholderIsNotReplaced(String text, String expected) {
-			PlaceholderResolver resolver = mockPlaceholderResolver(
-					"firstName", "John", "nested0", "first", "nested1", "Name",
+			Map<String, String> properties = Map.of(
+					"firstName", "John",
 					"${test}", "John",
-					"p1", "v1", "p2", "\\${p1:default}", "p3", "${p2}",
+					"p1", "v1",
+					"p2", "\\${p1:default}",
+					"p3", "${p2}",
 					"p4", "adc${p0:\\${p1}}",
 					"p5", "adc${\\${p0}:${p1}}",
 					"p6", "adc${p0:def\\${p1}}",
 					"p7", "adc\\${");
-			assertThat(this.parser.replacePlaceholders(text, resolver)).isEqualTo(expected);
+			assertThat(this.parser.replacePlaceholders(text, properties::get)).isEqualTo(expected);
 		}
 
 		static Stream<Arguments> escapedPlaceholders() {
@@ -324,18 +298,21 @@ class PlaceholderParserTests {
 					Arguments.of("${p4}", "adc${p1}"),
 					Arguments.of("${p5}", "adcv1"),
 					Arguments.of("${p6}", "adcdef${p1}"),
-					Arguments.of("${p7}", "adc\\${"));
-
+					Arguments.of("${p7}", "adc\\${"),
+					// Double backslash
+					Arguments.of("DOMAIN\\\\${user.name}", "DOMAIN\\${user.name}"),
+					// Triple backslash
+					Arguments.of("triple\\\\\\${backslash}", "triple\\\\${backslash}"),
+					// Multiple escaped placeholders
+					Arguments.of("start\\${prop1}middle\\${prop2}end", "start${prop1}middle${prop2}end")
+				);
 		}
 
 		@ParameterizedTest(name = "{0} -> {1}")
 		@MethodSource("escapedSeparators")
 		void escapedSeparatorIsNotReplaced(String text, String expected) {
-			Properties properties = new Properties();
-			properties.setProperty("first:Name", "John");
-			properties.setProperty("nested0", "first");
-			properties.setProperty("nested1", "Name");
-			assertThat(this.parser.replacePlaceholders(text, properties::getProperty)).isEqualTo(expected);
+			Map<String, String> properties = Map.of("first:Name", "John");
+			assertThat(this.parser.replacePlaceholders(text, properties::get)).isEqualTo(expected);
 		}
 
 		static Stream<Arguments> escapedSeparators() {
@@ -345,6 +322,26 @@ class PlaceholderParserTests {
 			);
 		}
 
+		@ParameterizedTest(name = "{0} -> {1}")
+		@MethodSource("escapedSeparatorsInNestedPlaceholders")
+		void escapedSeparatorInNestedPlaceholderIsNotReplaced(String text, String expected) {
+			Map<String, String> properties = Map.of(
+					"app.environment", "qa",
+					"app.service", "protocol",
+					"protocol://host/qa/name", "protocol://example.com/qa/name",
+					"service/host/qa/name", "https://example.com/qa/name",
+					"service/host/qa/name:value", "https://example.com/qa/name-value");
+			assertThat(this.parser.replacePlaceholders(text, properties::get)).isEqualTo(expected);
+		}
+
+		static Stream<Arguments> escapedSeparatorsInNestedPlaceholders() {
+			return Stream.of(
+					Arguments.of("${protocol\\://host/${app.environment}/name}", "protocol://example.com/qa/name"),
+					Arguments.of("${${app.service}\\://host/${app.environment}/name}", "protocol://example.com/qa/name"),
+					Arguments.of("${service/host/${app.environment}/name:\\value}", "https://example.com/qa/name"),
+					Arguments.of("${service/host/${name\\:value}/}", "${service/host/${name:value}/}"));
+		}
+
 	}
 
 	@Nested
@@ -354,34 +351,38 @@ class PlaceholderParserTests {
 
 		@Test
 		void textWithCircularReference() {
-			PlaceholderResolver resolver = mockPlaceholderResolver("pL", "${pR}", "pR", "${pL}");
-			assertThatThrownBy(() -> this.parser.replacePlaceholders("${pL}", resolver))
+			Map<String, String> properties = Map.of(
+					"pL", "${pR}",
+					"pR", "${pL}");
+			assertThatThrownBy(() -> this.parser.replacePlaceholders("${pL}", properties::get))
 					.isInstanceOf(PlaceholderResolutionException.class)
 					.hasMessage("Circular placeholder reference 'pL' in value \"${pL}\" <-- \"${pR}\" <-- \"${pL}\"");
 		}
 
 		@Test
 		void unresolvablePlaceholderIsReported() {
-			PlaceholderResolver resolver = mockPlaceholderResolver();
 			assertThatExceptionOfType(PlaceholderResolutionException.class)
-					.isThrownBy(() -> this.parser.replacePlaceholders("${bogus}", resolver))
-					.withMessage("Could not resolve placeholder 'bogus' in value \"${bogus}\"")
+					.isThrownBy(() -> this.parser.replacePlaceholders("X${bogus}Z", placeholderName -> null))
+					.withMessage("Could not resolve placeholder 'bogus' in value \"X${bogus}Z\"")
 					.withNoCause();
 		}
 
 		@Test
 		void unresolvablePlaceholderInNestedPlaceholderIsReportedWithChain() {
-			PlaceholderResolver resolver = mockPlaceholderResolver("p1", "v1", "p2", "v2",
+			Map<String, String> properties = Map.of(
+					"p1", "v1",
+					"p2", "v2",
 					"p3", "${p1}:${p2}:${bogus}");
 			assertThatExceptionOfType(PlaceholderResolutionException.class)
-					.isThrownBy(() -> this.parser.replacePlaceholders("${p3}", resolver))
+					.isThrownBy(() -> this.parser.replacePlaceholders("${p3}", properties::get))
 					.withMessage("Could not resolve placeholder 'bogus' in value \"${p1}:${p2}:${bogus}\" <-- \"${p3}\"")
 					.withNoCause();
 		}
 
 	}
 
-	PlaceholderResolver mockPlaceholderResolver(String... pairs) {
+
+	private static PlaceholderResolver mockPlaceholderResolver(String... pairs) {
 		if (pairs.length % 2 == 1) {
 			throw new IllegalArgumentException("size must be even, it is a set of key=value pairs");
 		}
@@ -394,7 +395,7 @@ class PlaceholderParserTests {
 		return resolver;
 	}
 
-	void verifyPlaceholderResolutions(PlaceholderResolver mock, String... placeholders) {
+	private static void verifyPlaceholderResolutions(PlaceholderResolver mock, String... placeholders) {
 		InOrder ordered = inOrder(mock);
 		for (String placeholder : placeholders) {
 			ordered.verify(mock).resolvePlaceholder(placeholder);