From bdfafcad7ef49bcf4d6fc2f6edde47c9b265ec81 Mon Sep 17 00:00:00 2001
From: huifer <huifer97@163.com>
Date: Sat, 10 Oct 2020 15:05:33 +0800
Subject: [PATCH] doc: PropertySource

---
 .../Spring-CommandLinePropertySource.md       | 127 +++++++++
 .../Spring-ComparisonPropertySource.md        |  44 ++++
 .../Spring-CompositePropertySource.md         | 105 ++++++++
 .../Spring-EnumerablePropertySource.md        |  46 ++++
 .../Spring-MapPropertySource.md               |  43 ++++
 .../Spring-MockPropertySource.md              | 112 ++++++++
 .../Spring-PropertiesPropertySource.md        |  35 +++
 .../Spring-ResourcePropertySource.md          | 241 ++++++++++++++++++
 .../Spring-ServletConfigPropertySource.md     |  36 +++
 .../Spring-ServletContextPropertySource.md    |  37 +++
 .../Spring-SimpleCommandLineArgsParser.md     |  55 ++++
 .../Spring-SimpleCommandLinePropertySource.md | 175 +++++++++++++
 .../Spring-StubPropertySource.md              |  28 ++
 13 files changed, 1084 insertions(+)
 create mode 100644 docs/Spring/clazz/PropertySource/Spring-CommandLinePropertySource.md
 create mode 100644 docs/Spring/clazz/PropertySource/Spring-ComparisonPropertySource.md
 create mode 100644 docs/Spring/clazz/PropertySource/Spring-CompositePropertySource.md
 create mode 100644 docs/Spring/clazz/PropertySource/Spring-EnumerablePropertySource.md
 create mode 100644 docs/Spring/clazz/PropertySource/Spring-MapPropertySource.md
 create mode 100644 docs/Spring/clazz/PropertySource/Spring-MockPropertySource.md
 create mode 100644 docs/Spring/clazz/PropertySource/Spring-PropertiesPropertySource.md
 create mode 100644 docs/Spring/clazz/PropertySource/Spring-ResourcePropertySource.md
 create mode 100644 docs/Spring/clazz/PropertySource/Spring-ServletConfigPropertySource.md
 create mode 100644 docs/Spring/clazz/PropertySource/Spring-ServletContextPropertySource.md
 create mode 100644 docs/Spring/clazz/PropertySource/Spring-SimpleCommandLineArgsParser.md
 create mode 100644 docs/Spring/clazz/PropertySource/Spring-SimpleCommandLinePropertySource.md
 create mode 100644 docs/Spring/clazz/PropertySource/Spring-StubPropertySource.md

diff --git a/docs/Spring/clazz/PropertySource/Spring-CommandLinePropertySource.md b/docs/Spring/clazz/PropertySource/Spring-CommandLinePropertySource.md
new file mode 100644
index 0000000..ee6e22b
--- /dev/null
+++ b/docs/Spring/clazz/PropertySource/Spring-CommandLinePropertySource.md
@@ -0,0 +1,127 @@
+# Spring CommandLinePropertySource
+
+- Author: [HuiFer](https://github.com/huifer)
+- 源码阅读仓库: [SourceHot-spring](https://github.com/SourceHot/spring-framework-read)
+
+
+- 类全路径: `org.springframework.core.env.CommandLinePropertySource`
+- 作用: 用来存储命令行参数
+
+
+
+
+
+```java
+public abstract class CommandLinePropertySource<T> extends EnumerablePropertySource<T> {
+
+   public static final String COMMAND_LINE_PROPERTY_SOURCE_NAME = "commandLineArgs";
+
+   public static final String DEFAULT_NON_OPTION_ARGS_PROPERTY_NAME = "nonOptionArgs";
+
+
+   private String nonOptionArgsPropertyName = DEFAULT_NON_OPTION_ARGS_PROPERTY_NAME;
+
+
+
+   public CommandLinePropertySource(T source) {
+      // 命令行参数, 属性值
+      super(COMMAND_LINE_PROPERTY_SOURCE_NAME, source);
+   }
+
+   public CommandLinePropertySource(String name, T source) {
+      // 参数名称, 参数值
+      super(name, source);
+   }
+
+
+   public void setNonOptionArgsPropertyName(String nonOptionArgsPropertyName) {
+      this.nonOptionArgsPropertyName = nonOptionArgsPropertyName;
+   }
+
+   @Override
+   public final boolean containsProperty(String name) {
+      // 输入值是否等于nonOptionArgs
+      if (this.nonOptionArgsPropertyName.equals(name)) {
+         // 等于后判断参数列表是否为空
+         return !this.getNonOptionArgs().isEmpty();
+      }
+      // 是否存在 name 属性
+      return this.containsOption(name);
+   }
+
+   @Override
+   @Nullable
+   public final String getProperty(String name) {
+      if (this.nonOptionArgsPropertyName.equals(name)) {
+         // 获取 非可选项参数列表
+         Collection<String> nonOptionArguments = this.getNonOptionArgs();
+         if (nonOptionArguments.isEmpty()) {
+            return null;
+         }
+         else {
+            // 可选参数命令行参数
+            return StringUtils.collectionToCommaDelimitedString(nonOptionArguments);
+         }
+      }
+      Collection<String> optionValues = this.getOptionValues(name);
+      if (optionValues == null) {
+         return null;
+      }
+      else {
+         // 命令行参数
+         return StringUtils.collectionToCommaDelimitedString(optionValues);
+      }
+   }
+
+
+   /**
+    * 是否存在 name 的命令行参数
+    */
+   protected abstract boolean containsOption(String name);
+
+   /**
+    * 获取参数列表集合
+    */
+   @Nullable
+   protected abstract List<String> getOptionValues(String name);
+
+   /**
+    * 获取 non-option 参数列表
+    */
+   protected abstract List<String> getNonOptionArgs();
+
+}
+```
+
+
+
+
+
+## getOptionValues
+
+```java
+/**
+ * Return the collection of values associated with the command line option having the
+ * given name.
+ * <ul>
+ * <li>if the option is present and has no argument (e.g.: "--foo"), return an empty
+ * collection ({@code []})</li>
+ * <li>if the option is present and has a single value (e.g. "--foo=bar"), return a
+ * collection having one element ({@code ["bar"]})</li>
+ * <li>if the option is present and the underlying command line parsing library
+ * supports multiple arguments (e.g. "--foo=bar --foo=baz"), return a collection
+ * having elements for each value ({@code ["bar", "baz"]})</li>
+ * <li>if the option is not present, return {@code null}</li>
+ * </ul>
+ *
+ * 获取参数列表集合
+ */
+@Nullable
+protected abstract List<String> getOptionValues(String name);
+```
+
+
+
+阅读注释可以知道该方法可以获取命令行参数的列表. 
+
+- 如 `--foo`作为开头当输入命令行为 `--foo=bar --foo=baz` 在输入参数名称 `foo` 会得到数据`bar,baz` 
\ No newline at end of file
diff --git a/docs/Spring/clazz/PropertySource/Spring-ComparisonPropertySource.md b/docs/Spring/clazz/PropertySource/Spring-ComparisonPropertySource.md
new file mode 100644
index 0000000..832d131
--- /dev/null
+++ b/docs/Spring/clazz/PropertySource/Spring-ComparisonPropertySource.md
@@ -0,0 +1,44 @@
+# Spring ComparisonPropertySource
+
+- Author: [HuiFer](https://github.com/huifer)
+- 源码阅读仓库: [SourceHot-spring](https://github.com/SourceHot/spring-framework-read)
+
+
+- 整体代码如下.
+    - 下面几个调用方法会直接抛出异常
+        1. getSource
+        1. containsProperty
+        1. getProperty
+
+```java
+	static class ComparisonPropertySource extends StubPropertySource {
+
+		// 异常信息
+		private static final String USAGE_ERROR =
+				"ComparisonPropertySource instances are for use with collection comparison only";
+
+		public ComparisonPropertySource(String name) {
+			super(name);
+		}
+
+		@Override
+		public Object getSource() {
+			// 抛异常
+			throw new UnsupportedOperationException(USAGE_ERROR);
+		}
+
+		@Override
+		public boolean containsProperty(String name) {
+			// 抛异常
+			throw new UnsupportedOperationException(USAGE_ERROR);
+		}
+
+		@Override
+		@Nullable
+		public String getProperty(String name) {
+			// 抛异常
+			throw new UnsupportedOperationException(USAGE_ERROR);
+		}
+	}
+
+```
\ No newline at end of file
diff --git a/docs/Spring/clazz/PropertySource/Spring-CompositePropertySource.md b/docs/Spring/clazz/PropertySource/Spring-CompositePropertySource.md
new file mode 100644
index 0000000..62eb94a
--- /dev/null
+++ b/docs/Spring/clazz/PropertySource/Spring-CompositePropertySource.md
@@ -0,0 +1,105 @@
+# Spring CompositePropertySource
+- Author: [HuiFer](https://github.com/huifer)
+- 源码阅读仓库: [SourceHot-spring](https://github.com/SourceHot/spring-framework-read)
+
+
+- 全路径: `org.springframework.core.env.CompositePropertySource`
+
+- 整体代码如下
+```java
+public class CompositePropertySource extends EnumerablePropertySource<Object> {
+
+	/**
+	 * set 集合
+	 */
+	private final Set<PropertySource<?>> propertySources = new LinkedHashSet<>();
+
+
+	/**
+	 * Create a new {@code CompositePropertySource}.
+	 * @param name the name of the property source
+	 */
+	public CompositePropertySource(String name) {
+		super(name);
+	}
+
+
+	@Override
+	@Nullable
+	public Object getProperty(String name) {
+		// 循环
+		for (PropertySource<?> propertySource : this.propertySources) {
+			// 获取存储内容
+			Object candidate = propertySource.getProperty(name);
+			if (candidate != null) {
+				return candidate;
+			}
+		}
+		return null;
+	}
+
+	@Override
+	public boolean containsProperty(String name) {
+		for (PropertySource<?> propertySource : this.propertySources) {
+			// 是否存在name
+			if (propertySource.containsProperty(name)) {
+				return true;
+			}
+		}
+		return false;
+	}
+
+	@Override
+	public String[] getPropertyNames() {
+		Set<String> names = new LinkedHashSet<>();
+		for (PropertySource<?> propertySource : this.propertySources) {
+			// 类型不同抛出异常
+			if (!(propertySource instanceof EnumerablePropertySource)) {
+				throw new IllegalStateException(
+						"Failed to enumerate property names due to non-enumerable property source: " + propertySource);
+			}
+			// 批量添加
+			names.addAll(Arrays.asList(((EnumerablePropertySource<?>) propertySource).getPropertyNames()));
+		}
+		// 转换成 array
+		return StringUtils.toStringArray(names);
+	}
+
+
+	/**
+	 * Add the given {@link PropertySource} to the end of the chain.
+	 * @param propertySource the PropertySource to add
+	 */
+	public void addPropertySource(PropertySource<?> propertySource) {
+		this.propertySources.add(propertySource);
+	}
+
+	/**
+	 * Add the given {@link PropertySource} to the start of the chain.
+	 * @param propertySource the PropertySource to add
+	 * @since 4.1
+	 */
+	public void addFirstPropertySource(PropertySource<?> propertySource) {
+		// 头插
+		List<PropertySource<?>> existing = new ArrayList<>(this.propertySources);
+		this.propertySources.clear();
+		this.propertySources.add(propertySource);
+		this.propertySources.addAll(existing);
+	}
+
+	/**
+	 * Return all property sources that this composite source holds.
+	 * @since 4.1.1
+	 */
+	public Collection<PropertySource<?>> getPropertySources() {
+		return this.propertySources;
+	}
+
+
+	@Override
+	public String toString() {
+		return getClass().getSimpleName() + " {name='" + this.name + "', propertySources=" + this.propertySources + "}";
+	}
+
+}
+```
\ No newline at end of file
diff --git a/docs/Spring/clazz/PropertySource/Spring-EnumerablePropertySource.md b/docs/Spring/clazz/PropertySource/Spring-EnumerablePropertySource.md
new file mode 100644
index 0000000..1a9afec
--- /dev/null
+++ b/docs/Spring/clazz/PropertySource/Spring-EnumerablePropertySource.md
@@ -0,0 +1,46 @@
+# Spring EnumerablePropertySource
+
+- Author: [HuiFer](https://github.com/huifer)
+- 源码阅读仓库: [SourceHot-spring](https://github.com/SourceHot/spring-framework-read)
+
+- 全路径: `org.springframework.core.env.EnumerablePropertySource`
+- 在这个类中定义了一个抽象方法`getPropertyNames` 用来获取所有的 property 的名称
+
+```java
+	public abstract String[] getPropertyNames();
+```
+- 整体代码如下
+```java
+public abstract class EnumerablePropertySource<T> extends PropertySource<T> {
+
+	public EnumerablePropertySource(String name, T source) {
+		super(name, source);
+	}
+
+	protected EnumerablePropertySource(String name) {
+		super(name);
+	}
+
+
+	/**
+	 * Return whether this {@code PropertySource} contains a property with the given name.
+	 * <p>This implementation checks for the presence of the given name within the
+	 * {@link #getPropertyNames()} array.
+	 *
+	 * 在属性列表中是否存在 properties 
+	 * @param name the name of the property to find
+	 */
+	@Override
+	public boolean containsProperty(String name) {
+		return ObjectUtils.containsElement(getPropertyNames(), name);
+	}
+
+	/**
+	 * Return the names of all properties contained by the
+	 * 获取所有的 properties 名称
+	 * {@linkplain #getSource() source} object (never {@code null}).
+	 */
+	public abstract String[] getPropertyNames();
+
+}
+```
\ No newline at end of file
diff --git a/docs/Spring/clazz/PropertySource/Spring-MapPropertySource.md b/docs/Spring/clazz/PropertySource/Spring-MapPropertySource.md
new file mode 100644
index 0000000..f8db931
--- /dev/null
+++ b/docs/Spring/clazz/PropertySource/Spring-MapPropertySource.md
@@ -0,0 +1,43 @@
+# Spring MapPropertySource
+
+- Author: [HuiFer](https://github.com/huifer)
+- 源码阅读仓库: [SourceHot-spring](https://github.com/SourceHot/spring-framework-read)
+
+
+- 类全路径: `org.springframework.core.env.MapPropertySource`
+- 内部数据结构是一个`Map<String,Object>`
+    这是一个对map的操作.
+      
+- 整体代码如下.
+
+```java
+
+public class MapPropertySource extends EnumerablePropertySource<Map<String, Object>> {
+
+	public MapPropertySource(String name, Map<String, Object> source) {
+		super(name, source);
+	}
+
+
+	@Override
+	@Nullable
+	public Object getProperty(String name) {
+		// 从map中获取 name 对应的value
+		return this.source.get(name);
+	}
+
+	@Override
+	public boolean containsProperty(String name) {
+		// 判断是否存在 name 属性
+		return this.source.containsKey(name);
+	}
+
+	@Override
+	public String[] getPropertyNames() {
+		// 互殴去 map 的所有key
+		return StringUtils.toStringArray(this.source.keySet());
+	}
+
+}
+
+```
\ No newline at end of file
diff --git a/docs/Spring/clazz/PropertySource/Spring-MockPropertySource.md b/docs/Spring/clazz/PropertySource/Spring-MockPropertySource.md
new file mode 100644
index 0000000..4f1ef01
--- /dev/null
+++ b/docs/Spring/clazz/PropertySource/Spring-MockPropertySource.md
@@ -0,0 +1,112 @@
+# Spring MockPropertySource
+- Author: [HuiFer](https://github.com/huifer)
+- 源码阅读仓库: [SourceHot-spring](https://github.com/SourceHot/spring-framework-read)
+
+
+- 内部 source 是 Properties 类型
+
+
+
+
+
+
+
+## withProperty
+
+- 设置属性名称和属性值	
+
+```java
+public MockPropertySource withProperty(String name, Object value) {
+   this.setProperty(name, value);
+   return this;
+}
+```
+
+
+
+
+
+## setProperty
+
+```java
+public void setProperty(String name, Object value) {
+   this.source.put(name, value);
+}
+```
+
+
+
+
+
+## 完整代码
+
+
+
+```java
+public class MockPropertySource extends PropertiesPropertySource {
+
+   /**
+    * {@value} is the default name for {@link MockPropertySource} instances not
+    * otherwise given an explicit name.
+    * @see #MockPropertySource()
+    * @see #MockPropertySource(String)
+    */
+   public static final String MOCK_PROPERTIES_PROPERTY_SOURCE_NAME = "mockProperties";
+
+   /**
+    * Create a new {@code MockPropertySource} named {@value #MOCK_PROPERTIES_PROPERTY_SOURCE_NAME}
+    * that will maintain its own internal {@link Properties} instance.
+    */
+   public MockPropertySource() {
+      this(new Properties());
+   }
+
+   /**
+    * Create a new {@code MockPropertySource} with the given name that will
+    * maintain its own internal {@link Properties} instance.
+    * @param name the {@linkplain #getName() name} of the property source
+    */
+   public MockPropertySource(String name) {
+      this(name, new Properties());
+   }
+
+   /**
+    * Create a new {@code MockPropertySource} named {@value #MOCK_PROPERTIES_PROPERTY_SOURCE_NAME}
+    * and backed by the given {@link Properties} object.
+    * @param properties the properties to use
+    */
+   public MockPropertySource(Properties properties) {
+      this(MOCK_PROPERTIES_PROPERTY_SOURCE_NAME, properties);
+   }
+
+   /**
+    * Create a new {@code MockPropertySource} with the given name and backed by the given
+    * {@link Properties} object.
+    * @param name the {@linkplain #getName() name} of the property source
+    * @param properties the properties to use
+    */
+   public MockPropertySource(String name, Properties properties) {
+      super(name, properties);
+   }
+
+   /**
+    * Set the given property on the underlying {@link Properties} object.
+    */
+   public void setProperty(String name, Object value) {
+      // map 操作
+      this.source.put(name, value);
+   }
+
+   /**
+    * Convenient synonym for {@link #setProperty} that returns the current instance.
+    * Useful for method chaining and fluent-style use.
+    * 设置属性名称和属性值
+    * @return this {@link MockPropertySource} instance
+    */
+      public MockPropertySource withProperty(String name, Object value) {
+         this.setProperty(name, value);
+         return this;
+      }
+
+}
+```
\ No newline at end of file
diff --git a/docs/Spring/clazz/PropertySource/Spring-PropertiesPropertySource.md b/docs/Spring/clazz/PropertySource/Spring-PropertiesPropertySource.md
new file mode 100644
index 0000000..967a36e
--- /dev/null
+++ b/docs/Spring/clazz/PropertySource/Spring-PropertiesPropertySource.md
@@ -0,0 +1,35 @@
+# Spring PropertiesPropertySource
+- Author: [HuiFer](https://github.com/huifer)
+- 源码阅读仓库: [SourceHot-spring](https://github.com/SourceHot/spring-framework-read)
+
+
+- 全路径: `org.springframework.core.env.PropertiesPropertySource`
+
+
+
+- Properties 是map结构。可以做类型转换. 
+- getPropertyNames 就转换成了父类MapPropertySource的方法了
+  - map.keySet()
+
+```java
+public class PropertiesPropertySource extends MapPropertySource {
+
+   @SuppressWarnings({"rawtypes", "unchecked"})
+   public PropertiesPropertySource(String name, Properties source) {
+      super(name, (Map) source);
+   }
+
+   protected PropertiesPropertySource(String name, Map<String, Object> source) {
+      super(name, source);
+   }
+
+
+   @Override
+   public String[] getPropertyNames() {
+      synchronized (this.source) {
+         return super.getPropertyNames();
+      }
+   }
+
+}
+```
\ No newline at end of file
diff --git a/docs/Spring/clazz/PropertySource/Spring-ResourcePropertySource.md b/docs/Spring/clazz/PropertySource/Spring-ResourcePropertySource.md
new file mode 100644
index 0000000..9b29fad
--- /dev/null
+++ b/docs/Spring/clazz/PropertySource/Spring-ResourcePropertySource.md
@@ -0,0 +1,241 @@
+# Spring ResourcePropertySource 
+- Author: [HuiFer](https://github.com/huifer)
+- 源码阅读仓库: [SourceHot-spring](https://github.com/SourceHot/spring-framework-read)
+
+
+- 全路径: `org.springframework.core.io.support.ResourcePropertySource`
+
+- source 依然是map结构
+
+
+
+
+
+
+
+## getNameForResource
+
+```java
+private static String getNameForResource(Resource resource) {
+   // 获取 resource 的介绍
+   String name = resource.getDescription();
+   if (!StringUtils.hasText(name)) {
+      // 短类名+@+hashcode
+      name = resource.getClass().getSimpleName() + "@" + System.identityHashCode(resource);
+   }
+   return name;
+}
+```
+
+
+
+
+
+## withName
+
+- 创建 ResourcePropertySource 对象, 根据 name 属性
+
+```java
+public ResourcePropertySource withName(String name) {
+   if (this.name.equals(name)) {
+      return this;
+   }
+   // Store the original resource name if necessary...
+   if (this.resourceName != null) {
+      if (this.resourceName.equals(name)) {
+         return new ResourcePropertySource(this.resourceName, null, this.source);
+      }
+      else {
+         return new ResourcePropertySource(name, this.resourceName, this.source);
+      }
+   }
+   else {
+      // Current name is resource name -> preserve it in the extra field...
+      return new ResourcePropertySource(name, this.name, this.source);
+   }
+}
+```
+
+
+
+
+
+## 构造函数
+
+- 通过 location 字符串读取 resource
+
+```java
+public ResourcePropertySource(String name, String location, ClassLoader classLoader) throws IOException {
+   // 默认资源读取器读取 location 转换成 resource
+   this(name, new DefaultResourceLoader(classLoader).getResource(location));
+}
+```
+
+
+
+- 读取 resource 信息进行存储
+
+```java
+public ResourcePropertySource(String name, EncodedResource resource) throws IOException {
+   // 设置 name + map 对象
+   // map 对象是 资源信息
+   super(name, PropertiesLoaderUtils.loadProperties(resource));
+   // 获取 resource name
+   this.resourceName = getNameForResource(resource.getResource());
+}
+```
+
+
+
+## 完整代码
+
+```java
+public class ResourcePropertySource extends PropertiesPropertySource {
+
+   /** The original resource name, if different from the given name. */
+   @Nullable
+   private final String resourceName;
+
+
+   /**
+    * Create a PropertySource having the given name based on Properties
+    * loaded from the given encoded resource.
+    */
+   public ResourcePropertySource(String name, EncodedResource resource) throws IOException {
+      // 设置 name + map 对象
+      // map 对象是 资源信息
+      super(name, PropertiesLoaderUtils.loadProperties(resource));
+      // 获取 resource name
+      this.resourceName = getNameForResource(resource.getResource());
+   }
+
+   /**
+    * Create a PropertySource based on Properties loaded from the given resource.
+    * The name of the PropertySource will be generated based on the
+    * {@link Resource#getDescription() description} of the given resource.
+    */
+   public ResourcePropertySource(EncodedResource resource) throws IOException {
+      // 设置 key: name, resource 的 name
+      // 设置 value: resource 资源信息
+      super(getNameForResource(resource.getResource()), PropertiesLoaderUtils.loadProperties(resource));
+      this.resourceName = null;
+   }
+
+   /**
+    * Create a PropertySource having the given name based on Properties
+    * loaded from the given encoded resource.
+    */
+   public ResourcePropertySource(String name, Resource resource) throws IOException {
+      super(name, PropertiesLoaderUtils.loadProperties(new EncodedResource(resource)));
+      this.resourceName = getNameForResource(resource);
+   }
+
+   /**
+    * Create a PropertySource based on Properties loaded from the given resource.
+    * The name of the PropertySource will be generated based on the
+    * {@link Resource#getDescription() description} of the given resource.
+    */
+   public ResourcePropertySource(Resource resource) throws IOException {
+      super(getNameForResource(resource), PropertiesLoaderUtils.loadProperties(new EncodedResource(resource)));
+      this.resourceName = null;
+   }
+
+   /**
+    * Create a PropertySource having the given name based on Properties loaded from
+    * the given resource location and using the given class loader to load the
+    * resource (assuming it is prefixed with {@code classpath:}).
+    */
+   public ResourcePropertySource(String name, String location, ClassLoader classLoader) throws IOException {
+      // 默认资源读取器读取 location 转换成 resource
+      this(name, new DefaultResourceLoader(classLoader).getResource(location));
+   }
+
+   /**
+    * Create a PropertySource based on Properties loaded from the given resource
+    * location and use the given class loader to load the resource, assuming it is
+    * prefixed with {@code classpath:}. The name of the PropertySource will be
+    * generated based on the {@link Resource#getDescription() description} of the
+    * resource.
+    */
+   public ResourcePropertySource(String location, ClassLoader classLoader) throws IOException {
+      this(new DefaultResourceLoader(classLoader).getResource(location));
+   }
+
+   /**
+    * Create a PropertySource having the given name based on Properties loaded from
+    * the given resource location. The default thread context class loader will be
+    * used to load the resource (assuming the location string is prefixed with
+    * {@code classpath:}.
+    */
+   public ResourcePropertySource(String name, String location) throws IOException {
+      this(name, new DefaultResourceLoader().getResource(location));
+   }
+
+   /**
+    * Create a PropertySource based on Properties loaded from the given resource
+    * location. The name of the PropertySource will be generated based on the
+    * {@link Resource#getDescription() description} of the resource.
+    */
+   public ResourcePropertySource(String location) throws IOException {
+      this(new DefaultResourceLoader().getResource(location));
+   }
+
+   private ResourcePropertySource(String name, @Nullable String resourceName, Map<String, Object> source) {
+      super(name, source);
+      this.resourceName = resourceName;
+   }
+
+   /**
+    * Return the description for the given Resource; if the description is
+    * empty, return the class name of the resource plus its identity hash code.
+    * @see org.springframework.core.io.Resource#getDescription()
+    */
+   private static String getNameForResource(Resource resource) {
+      // 获取 resource 的介绍
+      String name = resource.getDescription();
+      if (!StringUtils.hasText(name)) {
+         // 短类名+@+hashcode
+         name = resource.getClass().getSimpleName() + "@" + System.identityHashCode(resource);
+      }
+      return name;
+   }
+
+   /**
+    * Return a potentially adapted variant of this {@link ResourcePropertySource},
+    * overriding the previously given (or derived) name with the specified name.
+    * @since 4.0.4
+    */
+   public ResourcePropertySource withName(String name) {
+      if (this.name.equals(name)) {
+         return this;
+      }
+      // Store the original resource name if necessary...
+      if (this.resourceName != null) {
+         if (this.resourceName.equals(name)) {
+            return new ResourcePropertySource(this.resourceName, null, this.source);
+         }
+         else {
+            return new ResourcePropertySource(name, this.resourceName, this.source);
+         }
+      }
+      else {
+         // Current name is resource name -> preserve it in the extra field...
+         return new ResourcePropertySource(name, this.name, this.source);
+      }
+   }
+
+   /**
+    * Return a potentially adapted variant of this {@link ResourcePropertySource},
+    * overriding the previously given name (if any) with the original resource name
+    * (equivalent to the name generated by the name-less constructor variants).
+    * @since 4.1
+    */
+   public ResourcePropertySource withResourceName() {
+      if (this.resourceName == null) {
+         return this;
+      }
+      return new ResourcePropertySource(this.resourceName, null, this.source);
+   }
+
+}
+```
\ No newline at end of file
diff --git a/docs/Spring/clazz/PropertySource/Spring-ServletConfigPropertySource.md b/docs/Spring/clazz/PropertySource/Spring-ServletConfigPropertySource.md
new file mode 100644
index 0000000..d832b8b
--- /dev/null
+++ b/docs/Spring/clazz/PropertySource/Spring-ServletConfigPropertySource.md
@@ -0,0 +1,36 @@
+# Spring ServletConfigPropertySource
+
+- Author: [HuiFer](https://github.com/huifer)
+- 源码阅读仓库: [SourceHot-spring](https://github.com/SourceHot/spring-framework-read)
+
+
+- 类全路径: `org.springframework.web.context.support.ServletConfigPropertySource`
+- 内部数据结构是 `ServletConfig`
+   
+
+- 整体代码如下
+
+```java
+
+public class ServletConfigPropertySource extends EnumerablePropertySource<ServletConfig> {
+
+	public ServletConfigPropertySource(String name, ServletConfig servletConfig) {
+		super(name, servletConfig);
+	}
+
+	@Override
+	public String[] getPropertyNames() {
+		// javax.servlet.ServletConfig.getInitParameterNames
+		return StringUtils.toStringArray(this.source.getInitParameterNames());
+	}
+
+	@Override
+	@Nullable
+	public String getProperty(String name) {
+		// javax.servlet.ServletConfig.getInitParameter
+		return this.source.getInitParameter(name);
+	}
+
+}
+
+```
\ No newline at end of file
diff --git a/docs/Spring/clazz/PropertySource/Spring-ServletContextPropertySource.md b/docs/Spring/clazz/PropertySource/Spring-ServletContextPropertySource.md
new file mode 100644
index 0000000..48382ae
--- /dev/null
+++ b/docs/Spring/clazz/PropertySource/Spring-ServletContextPropertySource.md
@@ -0,0 +1,37 @@
+# Spring ServletContextPropertySource
+
+
+- Author: [HuiFer](https://github.com/huifer)
+- 源码阅读仓库: [SourceHot-spring](https://github.com/SourceHot/spring-framework-read)
+
+
+- 类全路径: `org.springframework.web.context.support.ServletContextPropertySource`
+- 内部数据结构是 ServletContext 接口
+      
+- 整体代码如下.
+
+
+```java
+
+public class ServletContextPropertySource extends EnumerablePropertySource<ServletContext> {
+
+	public ServletContextPropertySource(String name, ServletContext servletContext) {
+		super(name, servletContext);
+	}
+
+	@Override
+	public String[] getPropertyNames() {
+		// javax.servlet.ServletContext.getInitParameterNames 方法调用
+		return StringUtils.toStringArray(this.source.getInitParameterNames());
+	}
+
+	@Override
+	@Nullable
+	public String getProperty(String name) {
+		// javax.servlet.ServletContext.getInitParameter
+		return this.source.getInitParameter(name);
+	}
+
+}
+
+```
\ No newline at end of file
diff --git a/docs/Spring/clazz/PropertySource/Spring-SimpleCommandLineArgsParser.md b/docs/Spring/clazz/PropertySource/Spring-SimpleCommandLineArgsParser.md
new file mode 100644
index 0000000..92f7014
--- /dev/null
+++ b/docs/Spring/clazz/PropertySource/Spring-SimpleCommandLineArgsParser.md
@@ -0,0 +1,55 @@
+# Spring SimpleCommandLineArgsParser
+
+
+- Author: [HuiFer](https://github.com/huifer)
+- 源码阅读仓库: [SourceHot-spring](https://github.com/SourceHot/spring-framework-read)
+
+
+
+- 类全路径: `org.springframework.core.env.SimpleCommandLineArgsParser
+- 类作用: 将命令行参数解析成 `org.springframework.core.env.CommandLineArgs`
+
+- 完整代码如下. 
+```java
+
+class SimpleCommandLineArgsParser {
+
+	/**
+	 * Parse the given {@code String} array based on the rules described {@linkplain
+	 * SimpleCommandLineArgsParser above}, returning a fully-populated
+	 * {@link CommandLineArgs} object.
+	 * @param args command line arguments, typically from a {@code main()} method
+	 */
+	public CommandLineArgs parse(String... args) {
+		CommandLineArgs commandLineArgs = new CommandLineArgs();
+		for (String arg : args) {
+			if (arg.startsWith("--")) {
+				String optionText = arg.substring(2, arg.length());
+				String optionName;
+				String optionValue = null;
+				if (optionText.contains("=")) {
+					optionName = optionText.substring(0, optionText.indexOf('='));
+					optionValue = optionText.substring(optionText.indexOf('=') + 1, optionText.length());
+				}
+				else {
+					optionName = optionText;
+				}
+				if (optionName.isEmpty() || (optionValue != null && optionValue.isEmpty())) {
+					throw new IllegalArgumentException("Invalid argument syntax: " + arg);
+				}
+				commandLineArgs.addOptionArg(optionName, optionValue);
+			}
+			else {
+				commandLineArgs.addNonOptionArg(arg);
+			}
+		}
+		return commandLineArgs;
+	}
+
+}
+
+```
+
+- 处理流程
+    1. 循环命令行参数列表
+    2. 去掉 `--` 和 `=` 获取参数名称和参数值放入结果集合
\ No newline at end of file
diff --git a/docs/Spring/clazz/PropertySource/Spring-SimpleCommandLinePropertySource.md b/docs/Spring/clazz/PropertySource/Spring-SimpleCommandLinePropertySource.md
new file mode 100644
index 0000000..73af289
--- /dev/null
+++ b/docs/Spring/clazz/PropertySource/Spring-SimpleCommandLinePropertySource.md
@@ -0,0 +1,175 @@
+# Spring SimpleCommandLinePropertySource
+
+- 全路径: `org.springframework.core.env.SimpleCommandLinePropertySource`
+
+
+
+```java
+public class SimpleCommandLinePropertySource extends CommandLinePropertySource<CommandLineArgs> {}
+```
+
+- SimpleCommandLinePropertySource 的source 类型是 CommandLineArgs 具体解释请看下面分析
+
+
+
+
+
+
+
+## CommandLineArgs
+
+两个内部属性
+
+```java
+class CommandLineArgs {
+	/**
+	 * 选项参数列表
+	 */
+	private final Map<String, List<String>> optionArgs = new HashMap<>();
+
+	/**
+	 * 非选项参数列表
+	 */
+	private final List<String> nonOptionArgs = new ArrayList<>();
+
+}
+```
+
+### addOptionArg
+
+添加 选项参数 
+
+```java
+public void addOptionArg(String optionName, @Nullable String optionValue) {
+   if (!this.optionArgs.containsKey(optionName)) {
+      this.optionArgs.put(optionName, new ArrayList<>());
+   }
+   if (optionValue != null) {
+      this.optionArgs.get(optionName).add(optionValue);
+   }
+}
+```
+
+
+
+### getOptionNames
+
+- 获取选项参数列表
+
+```java
+public Set<String> getOptionNames() {
+   return Collections.unmodifiableSet(this.optionArgs.keySet());
+}
+```
+
+
+
+
+
+- 其他方法不具体描述了，各位可以查看下面的代码
+
+
+
+```java
+class CommandLineArgs {
+
+   /**
+    * 选项参数列表
+    */
+   private final Map<String, List<String>> optionArgs = new HashMap<>();
+
+   /**
+    * 非选项参数列表
+    */
+   private final List<String> nonOptionArgs = new ArrayList<>();
+
+   /**
+    * Add an option argument for the given option name and add the given value to the
+    * list of values associated with this option (of which there may be zero or more).
+    * The given value may be {@code null}, indicating that the option was specified
+    * without an associated value (e.g. "--foo" vs. "--foo=bar").
+    *
+    * 添加 选项参数
+    */
+   public void addOptionArg(String optionName, @Nullable String optionValue) {
+      if (!this.optionArgs.containsKey(optionName)) {
+         this.optionArgs.put(optionName, new ArrayList<>());
+      }
+      if (optionValue != null) {
+         this.optionArgs.get(optionName).add(optionValue);
+      }
+   }
+
+   /**
+    * Return the set of all option arguments present on the command line.
+    * 获取选项参数列表
+    */
+   public Set<String> getOptionNames() {
+      return Collections.unmodifiableSet(this.optionArgs.keySet());
+   }
+
+   /**
+    * Return whether the option with the given name was present on the command line.
+    */
+   public boolean containsOption(String optionName) {
+      return this.optionArgs.containsKey(optionName);
+   }
+
+   /**
+    * Return the list of values associated with the given option. {@code null} signifies
+    * that the option was not present; empty list signifies that no values were associated
+    * with this option.
+    */
+   @Nullable
+   public List<String> getOptionValues(String optionName) {
+      return this.optionArgs.get(optionName);
+   }
+
+   /**
+    * Add the given value to the list of non-option arguments.
+    */
+   public void addNonOptionArg(String value) {
+      this.nonOptionArgs.add(value);
+   }
+
+   /**
+    * Return the list of non-option arguments specified on the command line.
+    */
+   public List<String> getNonOptionArgs() {
+      return Collections.unmodifiableList(this.nonOptionArgs);
+   }
+
+}
+```
+
+
+
+
+
+在了解 CommandLineArgs 类后再来看 SimpleCommandLinePropertySource 会相对容易. 内部的几个方法就是调用 CommandLineArgs  所提供的方法
+
+
+
+```java
+@Override
+public String[] getPropertyNames() {
+   return StringUtils.toStringArray(this.source.getOptionNames());
+}
+
+@Override
+protected boolean containsOption(String name) {
+   return this.source.containsOption(name);
+}
+
+@Override
+@Nullable
+protected List<String> getOptionValues(String name) {
+   return this.source.getOptionValues(name);
+}
+
+@Override
+protected List<String> getNonOptionArgs() {
+   return this.source.getNonOptionArgs();
+}
+```
+
diff --git a/docs/Spring/clazz/PropertySource/Spring-StubPropertySource.md b/docs/Spring/clazz/PropertySource/Spring-StubPropertySource.md
new file mode 100644
index 0000000..7c9529e
--- /dev/null
+++ b/docs/Spring/clazz/PropertySource/Spring-StubPropertySource.md
@@ -0,0 +1,28 @@
+# Spring StubPropertySource
+
+- Author: [HuiFer](https://github.com/huifer)
+- 源码阅读仓库: [SourceHot-spring](https://github.com/SourceHot/spring-framework-read)
+
+
+
+- 整体代码如下. 
+    - 通过 StubPropertySource 的 getProperty 方法永远返回null
+
+```java
+	public static class StubPropertySource extends PropertySource<Object> {
+
+		public StubPropertySource(String name) {
+			super(name, new Object());
+		}
+
+		/**
+		 * Always returns {@code null}.
+		 */
+		@Override
+		@Nullable
+		public String getProperty(String name) {
+			return null;
+		}
+	}
+
+```
\ No newline at end of file