update:demo4

.gitignore

@@ -1 +1,95 @@
+### Compiled class files
+*.class
+
+### Log files
+*.log
+
+### BlueJ files
+*.ctxt
+
+### Mobile Tools for Java (J2ME)
+.mtj.tmp/
+
+### Package Files
+*.jar
+*.war
+*.nar
+*.ear
+*.zip
+*.tar.gz
+*.rar
+
+### VM crash logs
+hs_err_pid*
+replay_pid*
+
+# ========================
+# Maven
+# ========================
+target/
+pom.xml.tag
+pom.xml.releaseBackup
+pom.xml.versionsBackup
+pom.xml.next
+release.properties
+dependency-reduced-pom.xml
+buildNumber.properties
+.mvn/timing.properties
+.mvn/wrapper/maven-wrapper.jar
+
+# ========================
+# Gradle
+# ========================
+.gradle/
+build/
+!gradle-wrapper.jar
+!*/src/main/**/build/
+!*/src/test/**/build/
+
+### Avoid ignoring Gradle wrapper
+gradle-app.setting
+
+# ========================
+# IntelliJ IDEA
+# ========================
+.idea/
+*.iml
+*.ipr
+*.iws
+out/
+
+# ========================
+# Eclipse
+# ========================
+.project
+.classpath
+.cproject
+.settings/
+bin/
+tmp/
+
+# ========================
+# NetBeans
+# ========================
+nbproject/private/
+nbbuild/
+dist/
+nbdist/
+.nb-gradle/
+
+# ========================
+# VS Code
+# ========================
+.vscode/
+
+# ========================
+# OS files
+# ========================
+# macOS
+.DS_Store
+
+# Windows
+Thumbs.db
+
+#local
 com/study/test/