excel-utils

<properties>
        <poi.version>3.15</poi.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.apache.poi</groupId>
            <artifactId>poi-scratchpad</artifactId>
            <version>${poi.version}</version>
        </dependency>

        <dependency>
            <groupId>org.apache.poi</groupId>
            <artifactId>ooxml-schemas</artifactId>
            <version>1.3</version>
        </dependency>

        <dependency>
            <groupId>org.apache.poi</groupId>
            <artifactId>poi-ooxml</artifactId>
            <version>${poi.version}</version>
            <exclusions>
                <exclusion>
                    <groupId>org.apache.poi</groupId>
                    <artifactId>poi-ooxml-schemas</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
    </dependencies>

//通过文件系统的方式, 最大扫描行，最大扫描列
TemplateExcelUtils.builder()
    				.setFileSystemTemplate("D:/template.xlsx", 2, 3);
//在web环境下的方式, 最大扫描行，最大扫描列
TemplateExcelUtils.builder().
    				.setClassTemplatePath("/template.xlsx", 2, 3);

//添加键值数据
Map<String, String> data = new HashMap<>();
data.put("name", "xiaoming");
data.put("title", "The title");
TempalteExcelUtils.builder().
    				.setFileSystemTemplate("D:/template.xlsx", 2, 3)
    				.addValueData(data);

public class Table{
    //键序列, 通过这个序列依次再rowDataList中取值
    private List<String> keySequence;
    //表头数据
    private List<String> headers;
    //行数据
    private List<Map<String, String>> rowDataList;

    public Table(List<String> keySequence, List<String> headers, List<Map<String, String>> rowDataList) {
        this.keySequence = keySequence;
        this.headers = headers;
        this.rowDataList = rowDataList;
    }

    public Table(List<String> keySequence, List<Map<String, String>> rowDataList) {
        this.keySequence = keySequence;
        this.rowDataList = rowDataList;
    }
    
    /**
     *   getter/setter
     */
}

//......

//实例表格数据
List<Map<String, String>> rows = new ArrayList<>();
Map<String, String> row = new HashMap<>();
row.put("field1", "data1");
row.put("field2", "data2");
rows.add(row);
Table table = new Table(Arrays.asList("field1", "field2"), rows);

TempalteExcelUtils.builder().
    				.setFileSystemTemplate("D:/template.xlsx", 2, 3)
					.addValueData(data)
					.addMergerTableData("table1", table);

/**
 * 一次调用addMergerTableData 添加表数据，则是将这些表格数据合并； 
 * 多次调用addMergerTableData 添加表数据，则是分别添加。
 * addMergerTableData(String tableName, Table... table);
 */

//...

//调用build构建excel
TempalteExcelUtils.builder().
    				.addValueData(data);
					.addMergerTableData("table1", table);
					.build()

//...

OutputStream out = new FileOutputStream("D:/new.xlsx");
TempalteExcelUtils.builder().
    				.addValueData(data);
					.addMergerTableData("table1", table);
					.build()
                    .export(out);