feat:[Java 中拼接 String 的 N 种方式](https://www.wdbyte.com/java/string-concat.html)

niumoo · niumoo · commit ca34b424adbe · 2022-02-16T22:19:36.000+08:00
diff --git a/README.md b/README.md
@@ -141,7 +141,7 @@ Java 版本任你发，我用 Java 8 。但是多学点这种装x技巧总没错
 - 图
 
 ## ⏳ Java 开发
-
+- [Java 中拼接 String 的 N 种方式](https://www.wdbyte.com/java/string-concat.html)
 - [字符图案，我用字符画个冰墩墩](https://www.wdbyte.com/java/char-image.html)
 - [Java 中 RMI 的使用](https://www.wdbyte.com/2021/05/java/java-rmi/)
 - [如何使用 Github Actions 自动抓取每日必应壁纸?](https://www.wdbyte.com/2021/03/bing-wallpaper-github-action/)
diff --git a/core-java-modules/core-java-string/README.md b/core-java-modules/core-java-string/README.md
@@ -0,0 +1,6 @@
+## core-java-io
+当前模块包含 String 相关代码
+
+### 相关文章
+
+- [Java 中拼接 String 的 N 种方式](https://www.wdbyte.com/java/string-concat.html)
diff --git a/core-java-modules/core-java-string/pom.xml b/core-java-modules/core-java-string/pom.xml
@@ -0,0 +1,19 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <parent>
+        <artifactId>core-java-modules</artifactId>
+        <groupId>com.wdbyte.core-java-modules</groupId>
+        <version>1.0.0-SNAPSHOT</version>
+    </parent>
+    <modelVersion>4.0.0</modelVersion>
+
+    <artifactId>core-java-string</artifactId>
+
+    <properties>
+        <maven.compiler.source>17</maven.compiler.source>
+        <maven.compiler.target>17</maven.compiler.target>
+    </properties>
+
+</project>
diff --git a/core-java-modules/core-java-string/src/main/java/com/wdbyte/string/StringConcat.java b/core-java-modules/core-java-string/src/main/java/com/wdbyte/string/StringConcat.java
@@ -0,0 +1,88 @@
+package com.wdbyte.string;
+
+import java.util.Arrays;
+import java.util.Objects;
+import java.util.StringJoiner;
+import java.util.stream.Collectors;
+
+/**
+ * @author niulang
+ * @date 2022/02/16
+ */
+public class StringConcat {
+
+    public static void main(String[] args) {
+        System.out.println(concat());
+        System.out.println(concat2());
+        System.out.println(concat3());
+        System.out.println(concat4());
+        System.out.println(concat5());
+        System.out.println(concat6());
+        System.out.println(concat7());
+    }
+
+    public static String concat() {
+        String[] values = {"https", "://", "www.", "wdbyte", ".com", null};
+        String result = "";
+
+        for (String value : values) {
+            result = result + value;
+        }
+        return result;
+    }
+
+    public static String concat2() {
+        String[] values = {"https", "://", "www.", "wdbyte", ".com", null};
+        String result = String.join("", values);
+        return result;
+    }
+
+    public static String concat3() {
+        String[] values = {"https", "://", "www.", "wdbyte", ".com", null};
+        String result = "";
+        for (String value : values) {
+            result = result + nullToString(value);
+        }
+        return result;
+    }
+
+    public static String concat4() {
+        String[] values = {"https", "://", "www.", "wdbyte", ".com", null};
+        String result = "";
+        for (String value : values) {
+            result = result.concat(nullToString(value));
+        }
+        return result;
+    }
+
+    public static String concat5() {
+        String[] values = {"https", "://", "www.", "wdbyte", ".com", null};
+        StringBuilder result = new StringBuilder();
+        for (String value : values) {
+            result = result.append(nullToString(value));
+        }
+        return result.toString();
+    }
+
+    public static String concat6() {
+        String[] values = {"https", "://", "www.", "wdbyte", ".com", null};
+        StringJoiner result = new StringJoiner("");
+        for (String value : values) {
+            result = result.add(nullToString(value));
+        }
+        return result.toString();
+    }
+
+    public static String concat7() {
+        String[] values = {"https", "://", "www.", "wdbyte", ".com", null};
+        String result = Arrays.stream(values)
+            .filter(Objects::nonNull)
+            .collect(Collectors.joining());
+        return result;
+    }
+
+    public static String nullToString(String value) {
+        return value == null ? "" : value;
+    }
+
+}
