From 1029bc74f2554feeb899397761d9ca54e8437939 Mon Sep 17 00:00:00 2001
From: mawanli <mawl1@yusys.com.cn>
Date: Wed, 23 Jun 2021 11:28:20 +0800
Subject: [PATCH] =?UTF-8?q?1.[=E6=96=B0=E7=89=B9=E6=80=A7]=20CsvWriter?=
 =?UTF-8?q?=E6=B7=BB=E5=8A=A0writeBeans=E6=96=B9=E6=B3=95=EF=BC=8C?=
 =?UTF-8?q?=E6=A0=B9=E6=8D=AEBean=E8=87=AA=E5=8A=A8=E7=94=9F=E6=88=90?=
 =?UTF-8?q?=E8=A1=A8=E5=A4=B4=EF=BC=8C=E5=B9=B6=E5=86=99=E5=85=A5=E6=95=B0?=
 =?UTF-8?q?=E6=8D=AE?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../cn/hutool/core/text/csv/CsvWriter.java    | 23 ++++++++
 .../cn/hutool/core/text/csv/CsvUtilTest.java  | 56 +++++++++++++++++++
 2 files changed, 79 insertions(+)

diff --git a/hutool-core/src/main/java/cn/hutool/core/text/csv/CsvWriter.java b/hutool-core/src/main/java/cn/hutool/core/text/csv/CsvWriter.java
index 60d27685b..d55e25b7f 100644
--- a/hutool-core/src/main/java/cn/hutool/core/text/csv/CsvWriter.java
+++ b/hutool-core/src/main/java/cn/hutool/core/text/csv/CsvWriter.java
@@ -1,5 +1,6 @@
 package cn.hutool.core.text.csv;
 
+import cn.hutool.core.bean.BeanUtil;
 import cn.hutool.core.collection.CollUtil;
 import cn.hutool.core.convert.Convert;
 import cn.hutool.core.io.FileUtil;
@@ -18,7 +19,10 @@ import java.io.IOException;
 import java.io.Serializable;
 import java.io.Writer;
 import java.nio.charset.Charset;
+import java.util.ArrayList;
 import java.util.Collection;
+import java.util.List;
+import java.util.stream.Collectors;
 
 /**
  * CSV数据写出器
@@ -205,6 +209,25 @@ public final class CsvWriter implements Closeable, Flushable, Serializable {
 		return this;
 	}
 
+	/**
+	 * 将一个Bean集合写出到Writer，并自动生成表头
+	 *
+	 * @param beans Bean集合
+	 * @return this
+	 */
+	public CsvWriter writeBeans(Collection<?> beans) {
+		if (CollUtil.isNotEmpty(beans)) {
+			List<Collection<Object>> res = new ArrayList<>();
+			for (Object bean : beans) {
+				res.add(BeanUtil.beanToMap(bean).keySet().stream().map(k -> (Object) k).collect(Collectors.toList()));
+				break;
+			}
+			res.addAll(beans.stream().map(bean -> BeanUtil.beanToMap(bean).values()).collect(Collectors.toList()));
+			write(res);
+		}
+		return this;
+	}
+
 	/**
 	 * 写出一行
 	 *
diff --git a/hutool-core/src/test/java/cn/hutool/core/text/csv/CsvUtilTest.java b/hutool-core/src/test/java/cn/hutool/core/text/csv/CsvUtilTest.java
index 515f16707..1763061cd 100644
--- a/hutool-core/src/test/java/cn/hutool/core/text/csv/CsvUtilTest.java
+++ b/hutool-core/src/test/java/cn/hutool/core/text/csv/CsvUtilTest.java
@@ -61,6 +61,62 @@ public class CsvUtilTest {
 		);
 	}
 
+	@Test
+	@Ignore
+	public void writeBeansTest() {
+		class Student {
+			Integer id;
+			String name;
+			Integer age;
+
+			public Integer getId() {
+				return id;
+			}
+
+			public void setId(Integer id) {
+				this.id = id;
+			}
+
+			public String getName() {
+				return name;
+			}
+
+			public void setName(String name) {
+				this.name = name;
+			}
+
+			public Integer getAge() {
+				return age;
+			}
+
+			public void setAge(Integer age) {
+				this.age = age;
+			}
+		}
+		CsvWriter writer = CsvUtil.getWriter("d:/test/testWriteBeans.csv", CharsetUtil.CHARSET_UTF_8);
+		List<Student> students = new ArrayList<>();
+		Student student1 = new Student();
+		Student student2 = new Student();
+		Student student3 = new Student();
+
+		student1.setId(1);
+		student1.setName("张三");
+		student1.setAge(18);
+
+		student2.setId(2);
+		student2.setName("李四");
+		student2.setAge(22);
+
+		student3.setId(3);
+		student3.setName("王五");
+		student3.setAge(31);
+
+		students.add(student1);
+		students.add(student2);
+		students.add(student3);
+		writer.writeBeans(students);
+	}
+
 	@Test
 	@Ignore
 	public void readLfTest(){