diff --git a/spring-context/src/main/java/org/springframework/context/support/AbstractApplicationContext.java b/spring-context/src/main/java/org/springframework/context/support/AbstractApplicationContext.java
index df733ef60a435f92eee5bb499de0b846592edfa2..532637718602485ed1fca4baa99a7c209f75b865 100644
--- a/spring-context/src/main/java/org/springframework/context/support/AbstractApplicationContext.java
+++ b/spring-context/src/main/java/org/springframework/context/support/AbstractApplicationContext.java
@@ -226,6 +226,7 @@ public abstract class AbstractApplicationContext extends DefaultResourceLoader
 	 * Create a new AbstractApplicationContext with no parent.
 	 */
 	public AbstractApplicationContext() {
+		// 调用父类构造方法，设置类加载器
 		// 设置资源解析器，默认实现为 PathMatchingResourcePatternResolver
 		this.resourcePatternResolver = getResourcePatternResolver();
 	}
@@ -318,6 +319,7 @@ public abstract class AbstractApplicationContext extends DefaultResourceLoader
 	@Override
 	public ConfigurableEnvironment getEnvironment() {
 		if (this.environment == null) {
+			// 创建并返回一个新的StandardEnvironment
 			this.environment = createEnvironment();
 		}
 		return this.environment;
@@ -329,6 +331,7 @@ public abstract class AbstractApplicationContext extends DefaultResourceLoader
 	 * a custom {@link ConfigurableEnvironment} implementation.
 	 */
 	protected ConfigurableEnvironment createEnvironment() {
+		// 实例化StandardEnvironment对象，并设置java所使用属性资源 customizePropertySources
 		return new StandardEnvironment();
 	}
 
diff --git a/spring-context/src/main/java/org/springframework/context/support/AbstractRefreshableConfigApplicationContext.java b/spring-context/src/main/java/org/springframework/context/support/AbstractRefreshableConfigApplicationContext.java
index 35d2cfcfb7daa70b44fcf5b5964dfed57b1abcbc..d909c80bd52b485f303b9e70e10fd3425f40799d 100644
--- a/spring-context/src/main/java/org/springframework/context/support/AbstractRefreshableConfigApplicationContext.java
+++ b/spring-context/src/main/java/org/springframework/context/support/AbstractRefreshableConfigApplicationContext.java
@@ -123,6 +123,7 @@ public abstract class AbstractRefreshableConfigApplicationContext extends Abstra
 	 * @see org.springframework.core.env.Environment#resolveRequiredPlaceholders(String)
 	 */
 	protected String resolvePath(String path) {
+		// 创建上下文的Environment，并解析配置文件名
 		return getEnvironment().resolveRequiredPlaceholders(path);
 	}
 
diff --git a/spring-context/src/main/java/org/springframework/context/support/ClassPathXmlApplicationContext.java b/spring-context/src/main/java/org/springframework/context/support/ClassPathXmlApplicationContext.java
index ca984968afa0b9d7037b05f4a0e15ec72021827f..e10b101cd4291066f81de69cf806efe380213237 100644
--- a/spring-context/src/main/java/org/springframework/context/support/ClassPathXmlApplicationContext.java
+++ b/spring-context/src/main/java/org/springframework/context/support/ClassPathXmlApplicationContext.java
@@ -139,6 +139,7 @@ public class ClassPathXmlApplicationContext extends AbstractXmlApplicationContex
 			throws BeansException {
 		// 初始化父类属性值以及设置资源解析器
 		super(parent);
+		// 设置上下文环境，并解析配置文件
 		setConfigLocations(configLocations);
 		if (refresh) {
 			refresh();
diff --git a/spring-core/src/main/java/org/springframework/core/env/AbstractPropertyResolver.java b/spring-core/src/main/java/org/springframework/core/env/AbstractPropertyResolver.java
index c3f29e106ad90a81e1049a8422127eb7ae9b7347..4375c5516e0e72d089f5a7d4ab352e9af6a41cfe 100644
--- a/spring-core/src/main/java/org/springframework/core/env/AbstractPropertyResolver.java
+++ b/spring-core/src/main/java/org/springframework/core/env/AbstractPropertyResolver.java
@@ -205,6 +205,7 @@ public abstract class AbstractPropertyResolver implements ConfigurablePropertyRe
 	@Override
 	public String resolveRequiredPlaceholders(String text) throws IllegalArgumentException {
 		if (this.strictHelper == null) {
+			// 创建PlaceholderHelper组件，用于解析配置文件名，如设置${前缀等等...
 			this.strictHelper = createPlaceholderHelper(false);
 		}
 		return doResolvePlaceholders(text, this.strictHelper);