需求说明:公司做项目前进行需求分析,确定表结构后需要建表,如果照着表格去敲,那就太麻烦了,所以想到了自动生成SQL语句。
思路大概就是:解析Excel,拼接SQL语句,输出SQL文件。
第三方jar包:POI(解析Excel)
先建立一个maven项目。
pom依赖:
<?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">
<modelVersion>4.0.0</modelVersion>
<groupId>com.transition</groupId>
<artifactId>excel-to-sql</artifactId>
<version>1.0-SNAPSHOT</version>
<dependencies>
<!-- https://mvnrepository.com/artifact/org.apache.poi/poi -->
<dependency>
<groupId>org.apache.poi</groupId>
<artifactId>poi</artifactId>
<version>3.17</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.apache.poi/poi-ooxml -->
<dependency>
<groupId>org.apache.poi</groupId>
<artifactId>poi-ooxml</artifactId>
<version>3.17</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.apache.poi/poi-ooxml-schemas -->
<dependency>
<groupId>org.apache.poi</groupId>
<artifactId>poi-ooxml-schemas</artifactId>
<version>3.17</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.apache.xmlbeans/xmlbeans -->
<dependency>
<groupId>org.apache.xmlbeans</groupId>
<artifactId>xmlbeans</artifactId>
<version>2.6.0</version>
</dependency>
<!-- https://mvnrepository.com/artifact/dom4j/dom4j -->
<dependency>
<groupId>dom4j</groupId>
<artifactId>dom4j</artifactId>
<version>1.6.1</version>
</dependency>
</dependencies>
<build>
<plugins>
<!-- 编译插件 -->
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.7.0</version>
<configuration>
<source>1.8</source>
<target>1.8</target>
</configuration>
</plugin>
</plugins>
</build>
</project>
目录结构
Keys.Java
package com.transition.core.common;
public class Keys {
public static final String TABLE_PRE = "DROP TABLE IF EXISTS ";
public static final String TABLE_SUFF = "ENGINE=InnoDB DEFAULT CHARSET=utf8 COMMENT=";
public static final String C_T = "CREATE TABLE ";
public static final String N_N = " NOT NULL ";
public static final String A_I = "AUTO_INCREMENT";
public static final String P_K = "PRIMARY KEY ";
public static final String F_K = " FOREIGN KEY ";
public static final String COMMENT = " COMMENT ";
public static final String DEFAULT = " DEFAULT ";
}
DataTable.Java
package com.transition.core.entity;
import java.util.ArrayList;
import java.util.List;
/**
* 数据库表
*/
public class DataTable {
private String tableName; // 数据库表名
private String comment; //数据库注释
private List<TableField> fields = new ArrayList<>();
public DataTable() {
}
public DataTable(String tableName, String comment) {
this.tableName = tableName;
this.comment = comment;
}
public String getTableName() {
return tableName;
}
public void setTableName(String tableName) {
this.tableName = tableName;
}
public String getComment() {
return comment;
}
public void setComment(String comment) {
this.comment = comment;
}
public List<TableField> getFields() {
return fields;
}
public void setFields(List<TableField> fields) {
this.fields = fields;
}
@Override
public String toString() {
return "DataTable{" +
"tableName='" + tableName + '\'' +
", comment='" + comment + '\'' +
", fields=" + fields +
'}';
}
}
TableField.Java
package com.transition.core.entity;
/**
* 表字段
*/
public class TableField {
private String fieldName; // 字段名
private String fieldType; // 字段类型
private String isNull; // 是否为空
private String defaultValue;// 默认值
private String comment; // 注释
public TableField() {
}
public TableField(String fieldName, String fieldType, String isNull, String defaultValue, String comment) {
this.fieldName = fieldName;
this.fieldType = fieldType;
this.isNull = isNull;
this.defaultValue = defaultValue;
this.comment = comment;
}
public String getFieldName() {
return fieldName;
}
public void setFieldName(String fieldName) {
this.fieldName = fieldName;
}
public String getFieldType() {
return fieldType;
}
public void setFieldType(String fieldType) {
this.fieldType = fieldType;
}
public String getIsNull() {
return isNull;
}
public void setIsNull(String isNull) {
this.isNull = isNull;
}
public String getDefaultValue() {
return defaultValue;
}
public void setDefaultValue(String defaultValue) {
this.defaultValue = defaultValue;
}
public String getComment() {
return comment;
}
public void setComment(String comment) {
this.comment = comment;
}
@Override
public String toString() {
return "TableField{" +
"fieldName='" + fieldName + '\'' +
", fieldType='" + fieldType + '\'' +
", isNull='" + isNull + '\'' +
", defaultValue='" + defaultValue + '\'' +
", comment='" + comment + '\'' +
'}';
}
}
Core
package com.transition.core;
import com.transition.core.common.Keys;
import com.transition.core.entity.DataTable;
import com.transition.core.entity.TableField;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.CellType;
import org.apache.poi.xssf.usermodel.XSSFRow;
import org.apache.poi.xssf.usermodel.XSSFSheet;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
import java.io.*;
import java.util.ArrayList;
import java.util.List;
public class Core {
private static int tableNum = 0;
private static int sentry = -1; // 哨兵
public static List<DataTable> readXlsx(String path){
List<DataTable> list = new ArrayList<>();
System.out.println("读取...");
InputStream in = null;
try {
in = new FileInputStream(path);
XSSFWorkbook xss = new XSSFWorkbook(in);
for(int i = 0; i < xss.getNumberOfSheets(); i++){
XSSFSheet sheet = xss.getSheetAt(i);
if(sheet == null)
continue;
for(int r = 0; r <= sheet.getLastRowNum(); r++){
XSSFRow row = sheet.getRow(r);
if(row != null){
// 如果哨兵等于0,代表这一行是不需要读取的。continue之后自减1
if (sentry-- == 0){
continue;
}
/*
_NONE(-1),
NUMERIC(0),
STRING(1),
FORMULA(2),
BLANK(3),
BOOLEAN(4),
ERROR(5);
*/
CellType cellType2 = row.getCell(2).getCellTypeEnum();
CellType cellType3 = row.getCell(3).getCellTypeEnum();
CellType cellType4 = row.getCell(4).getCellTypeEnum();
if (cellType2 == CellType.BLANK && cellType3 == CellType.BLANK && cellType4 == CellType.BLANK){
++tableNum;
sentry = 0;
String name = row.getCell(0).getStringCellValue().toLowerCase();
String comment = row.getCell(1).getStringCellValue();
list.add(new DataTable(name, comment));
System.out.println("----------------------Table-------------------");
System.out.println("表名:" + name + ",注释:" + comment);
continue;
}
if(cellType3 == CellType.NUMERIC)
list.get(list.size()-1).getFields().add(new TableField(row.getCell(0).getStringCellValue(),
row.getCell(1).getStringCellValue(),
row.getCell(2).getStringCellValue(),
Math.round(row.getCell(3).getNumericCellValue())+"",
row.getCell(4).getStringCellValue()));
else
list.get(list.size()-1).getFields().add(new TableField(row.getCell(0).getStringCellValue(),
row.getCell(1).getStringCellValue(),
row.getCell(2).getStringCellValue(),
row.getCell(3).getStringCellValue(),
row.getCell(4).getStringCellValue()));
}
}
}
in.close();
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return list;
}
public static void exportToSQL(List<DataTable> list, String sqlPath) throws IOException {
final List<String> sql = new ArrayList<>();
list.forEach(e -> {
sentry = 1;
StringBuilder sb = new StringBuilder();
sb.append(Keys.TABLE_PRE + "`" + e.getTableName() + "`;\n");
sb.append(Keys.C_T + "`" + e.getTableName() + "` (\n");
e.getFields().forEach(c -> {
// 只有主键有自增
if (sentry == 1){
sb.append("`" + c.getFieldName().toLowerCase() + "` " + c.getFieldType().toLowerCase() + Keys.N_N + Keys.A_I + Keys.COMMENT + "'" + c.getComment() + "',\n");
sentry = 0;
}else {
// 如果无默认值
if (c.getDefaultValue() == null || c.getDefaultValue().equals("")){
// 如果不为空,或者无标志,一律按照不为空处理
if ("N".equals(c.getIsNull()) || "".equals(c.getIsNull()) || c.getIsNull() == null)
sb.append("`" + c.getFieldName().toLowerCase() + "` " + c.getFieldType().toLowerCase() + Keys.N_N + Keys.COMMENT + "'" + c.getComment() + "',\n");
else
sb.append("`" + c.getFieldName().toLowerCase() + "` " + c.getFieldType().toLowerCase() + Keys.COMMENT + "'" + c.getComment() + "',\n");
} else{
// 如果不为空,或者无标志,一律按照不为空处理
if ("N".equals(c.getIsNull()) || "".equals(c.getIsNull()) || c.getIsNull() == null)
sb.append("`" + c.getFieldName().toLowerCase() + "` " + c.getFieldType().toLowerCase() + Keys.N_N + Keys.DEFAULT + "'" + c.getDefaultValue() + "'" + Keys.COMMENT + "'" + c.getComment() + "',\n");
else
sb.append("`" + c.getFieldName().toLowerCase() + "` " + c.getFieldType().toLowerCase() + Keys.DEFAULT + "'" + c.getDefaultValue() + "'" + Keys.COMMENT + "'" + c.getComment() + "',\n");
}
}
});
sb.append(Keys.P_K + "(`" + e.getFields().get(0).getFieldName().toLowerCase() + "`)\n" +
") " + Keys.TABLE_SUFF + "'" + e.getComment() + "';\n\n");
System.out.println(sb.toString());
sql.add(sb.toString());
});
File file = new File(sqlPath);
FileOutputStream out = new FileOutputStream(file);
sql.forEach(s -> {
try {
out.write(s.getBytes());
} catch (IOException e) {
e.printStackTrace();
}
});
out.close();
}
public static int getTableNum() {
return tableNum;
}
}
RunApplication
package com.transition.core;
import com.transition.core.entity.DataTable;
import java.io.IOException;
import java.util.List;
public class RunApplication {
public static void main(String[] args) throws IOException {
List<DataTable> tables = Core.readXlsx("table2.xlsx");
// tables.forEach(e -> System.out.println(e));
Core.exportToSQL(tables,"test.sql");
System.out.println("TableNumber : " + Core.getTableNum());
}
}
我要读取table2.xlsx,输出到test.sql
运行,输出结果:
查看sql文件
在Navicat里面运行这个sql文件
可以看到,字段名全部是小写,类型,长度,字段注释都正确设置,是否为空也符合要求。
不过有个事情:如果你要添加外键依赖,触发器之类的要自己手动去配置。另外,这个代码有点特定为这种格式的表格,如果你不是这种结果的表格,很可能不成功。
如果你不会改就叫我好了
不过,如果你有很多表的话,帮你生成已经节省很多时间了,还要啥自行车啊
来源:oschina
链接:https://my.oschina.net/u/4363215/blog/4029054