diff --git a/README.md b/README.md
index b975eba74..c58f33376 100644
--- a/README.md
+++ b/README.md
@@ -161,8 +161,8 @@ Hutool欢迎任何人为Hutool添砖加瓦，贡献代码，不过作者是一
 
 1. 在Gitee或者Github上fork项目到自己的repo
 2. 把fork过去的项目也就是你的项目clone到你的本地
-3. 修改代码（记得一定要修改v4-dev分支）
-4. commit后push到自己的库（v4-dev分支）
+3. 修改代码（记得一定要修改v5-dev分支）
+4. commit后push到自己的库（v5-dev分支）
 5. 登录Gitee或Github在你首页可以看到一个 pull request 按钮，点击它，填写一些说明信息，然后提交即可。
 6. 等待作者合并
 
diff --git a/hutool-setting/src/main/java/cn/hutool/setting/AbsSetting.java b/hutool-setting/src/main/java/cn/hutool/setting/AbsSetting.java
index 9b12531c0..9466eceb9 100644
--- a/hutool-setting/src/main/java/cn/hutool/setting/AbsSetting.java
+++ b/hutool-setting/src/main/java/cn/hutool/setting/AbsSetting.java
@@ -266,11 +266,7 @@ public abstract class AbsSetting extends OptNullBasicTypeFromStringGetter<String
 
 			@Override
 			public Object value(String key, Type valueType) {
-				final String value = getByGroup(key, group);
-//				if (null != value) {
-//					log.debug("Parse setting to object field [{}={}]", key, value);
-//				}
-				return value;
+				return getByGroup(key, group);
 			}
 
 			@Override
diff --git a/hutool-setting/src/main/java/cn/hutool/setting/GroupedMap.java b/hutool-setting/src/main/java/cn/hutool/setting/GroupedMap.java
index 1ce948ca4..3689ce667 100644
--- a/hutool-setting/src/main/java/cn/hutool/setting/GroupedMap.java
+++ b/hutool-setting/src/main/java/cn/hutool/setting/GroupedMap.java
@@ -63,6 +63,7 @@ public class GroupedMap extends LinkedHashMap<String, LinkedHashMap<String, Stri
 	 * 
 	 * @return 总键值对数
 	 */
+	@Override
 	public int size() {
 		writeLock.lock();
 		try {
@@ -90,11 +91,7 @@ public class GroupedMap extends LinkedHashMap<String, LinkedHashMap<String, Stri
 		group = StrUtil.nullToEmpty(group).trim();
 		writeLock.lock();
 		try {
-			LinkedHashMap<String, String> valueMap = this.get(group);
-			if (null == valueMap) {
-				valueMap = new LinkedHashMap<>();
-				this.put(group, valueMap);
-			}
+			final LinkedHashMap<String, String> valueMap = this.computeIfAbsent(group, k -> new LinkedHashMap<>());
 			this.size = -1;
 			return valueMap.put(key, value);
 		} finally {
diff --git a/hutool-setting/src/main/java/cn/hutool/setting/GroupedSet.java b/hutool-setting/src/main/java/cn/hutool/setting/GroupedSet.java
index 6703e8830..13adfaf2e 100644
--- a/hutool-setting/src/main/java/cn/hutool/setting/GroupedSet.java
+++ b/hutool-setting/src/main/java/cn/hutool/setting/GroupedSet.java
@@ -199,7 +199,7 @@ public class GroupedSet extends HashMap<String, LinkedHashSet<String>> {
 		try {
 			reader = IoUtil.getReader(settingStream, charset);
 			// 分组
-			String group = null;
+			String group;
 			LinkedHashSet<String> valueSet = null;
 
 			while (true) {
@@ -223,7 +223,7 @@ public class GroupedSet extends HashMap<String, LinkedHashSet<String>> {
 					group = line.substring(1, line.length() - 1).trim();
 					valueSet = super.get(group);
 					if (null == valueSet) {
-						valueSet = new LinkedHashSet<String>();
+						valueSet = new LinkedHashSet<>();
 					}
 					super.put(group, valueSet);
 					continue;
@@ -232,7 +232,7 @@ public class GroupedSet extends HashMap<String, LinkedHashSet<String>> {
 				// 添加值
 				if (null == valueSet) {
 					// 当出现无分组值的时候，会导致valueSet为空，此时group为""
-					valueSet = new LinkedHashSet<String>();
+					valueSet = new LinkedHashSet<>();
 					super.put(StrUtil.EMPTY, valueSet);
 				}
 				valueSet.add(line);
diff --git a/hutool-setting/src/main/java/cn/hutool/setting/Setting.java b/hutool-setting/src/main/java/cn/hutool/setting/Setting.java
index 310f41555..69941d927 100644
--- a/hutool-setting/src/main/java/cn/hutool/setting/Setting.java
+++ b/hutool-setting/src/main/java/cn/hutool/setting/Setting.java
@@ -258,14 +258,14 @@ public class Setting extends AbsSetting implements Map<String, String> {
 	 * @since 3.1.2
 	 */
 	public String getAndRemoveStr(String... keys) {
-		Object value = null;
+		String value = null;
 		for (String key : keys) {
 			value = remove(key);
 			if (null != value) {
 				break;
 			}
 		}
-		return (String) value;
+		return value;
 	}
 
 	/**
@@ -276,7 +276,7 @@ public class Setting extends AbsSetting implements Map<String, String> {
 	 */
 	public Map<String, String> getMap(String group) {
 		final LinkedHashMap<String, String> map = this.groupedMap.get(group);
-		return (null != map) ? map : new LinkedHashMap<String, String>(0);
+		return (null != map) ? map : new LinkedHashMap<>(0);
 	}
 
 	/**
@@ -692,13 +692,10 @@ public class Setting extends AbsSetting implements Map<String, String> {
 			return false;
 		}
 		if (settingUrl == null) {
-			if (other.settingUrl != null) {
-				return false;
-			}
-		} else if (!settingUrl.equals(other.settingUrl)) {
-			return false;
+			return other.settingUrl == null;
+		} else {
+			return settingUrl.equals(other.settingUrl);
 		}
-		return true;
 	}
 
 	@Override
diff --git a/hutool-setting/src/main/java/cn/hutool/setting/SettingLoader.java b/hutool-setting/src/main/java/cn/hutool/setting/SettingLoader.java
index d2eef9471..c1021cd7a 100644
--- a/hutool-setting/src/main/java/cn/hutool/setting/SettingLoader.java
+++ b/hutool-setting/src/main/java/cn/hutool/setting/SettingLoader.java
@@ -202,7 +202,7 @@ public class SettingLoader {
 	 */
 	private String replaceVar(String group, String value) {
 		// 找到所有变量标识
-		final Set<String> vars = ReUtil.findAll(varRegex, value, 0, new HashSet<String>());
+		final Set<String> vars = ReUtil.findAll(varRegex, value, 0, new HashSet<>());
 		String key;
 		for (String var : vars) {
 			key = ReUtil.get(varRegex, var, 1);
diff --git a/hutool-setting/src/main/java/cn/hutool/setting/SettingUtil.java b/hutool-setting/src/main/java/cn/hutool/setting/SettingUtil.java
index 3a5ff1a94..2dfed771c 100644
--- a/hutool-setting/src/main/java/cn/hutool/setting/SettingUtil.java
+++ b/hutool-setting/src/main/java/cn/hutool/setting/SettingUtil.java
@@ -16,7 +16,7 @@ import cn.hutool.core.util.StrUtil;
 public class SettingUtil {
 	/** 配置文件缓存 */
 	private static Map<String, Setting> settingMap = new ConcurrentHashMap<>();
-	private static Object lock = new Object();
+	private static final Object lock = new Object();
 
 	/**
 	 * 获取当前环境下的配置文件<br>
diff --git a/hutool-system/src/main/java/cn/hutool/system/oshi/OshiUtil.java b/hutool-system/src/main/java/cn/hutool/system/oshi/OshiUtil.java
index 0a67ebd04..b44a11101 100644
--- a/hutool-system/src/main/java/cn/hutool/system/oshi/OshiUtil.java
+++ b/hutool-system/src/main/java/cn/hutool/system/oshi/OshiUtil.java
@@ -16,6 +16,8 @@ import oshi.software.os.OperatingSystem;
  * 1、系统信息
  * 2、硬件信息
  * </pre>
+ *
+ * 相关内容见：https://github.com/oshi/oshi
  * 
  * @author Looly
  * @since 4.6.4