插件代码：

import org.mybatis.generator.api.CommentGenerator;
import org.mybatis.generator.api.IntrospectedTable;
import org.mybatis.generator.api.PluginAdapter;
import org.mybatis.generator.api.dom.java.*;
import org.mybatis.generator.api.dom.xml.Attribute;
import org.mybatis.generator.api.dom.xml.TextElement;
import org.mybatis.generator.api.dom.xml.XmlElement;

import java.util.List;

/**
 * 分页插件
 * @author: Nemo
 * @date: 2018/3/27.
 */
public class MySQLPaginationPlugin extends PluginAdapter{

    @Override
    public boolean modelExampleClassGenerated(TopLevelClass topLevelClass, IntrospectedTable introspectedTable) {
        // add field, getter, setter for limit clause
        addLimit(topLevelClass, introspectedTable, "startIndex");
        addLimit(topLevelClass, introspectedTable, "pageSize");
        addLimitMethod(topLevelClass, introspectedTable);
        return super.modelExampleClassGenerated(topLevelClass, introspectedTable);
    }

    @Override
    public boolean sqlMapSelectByExampleWithoutBLOBsElementGenerated(XmlElement element, IntrospectedTable introspectedTable) {
        //$NON-NLS-1$
        XmlElement isNotNullElement = new XmlElement("if");
        //$NON-NLS-1$ //$NON-NLS-2$
        isNotNullElement.addAttribute(new Attribute("test", "startIndex >= 0"));
        isNotNullElement.addElement(new TextElement("limit ${startIndex} , ${pageSize}"));
        element.addElement(isNotNullElement);
        return super.sqlMapUpdateByExampleWithoutBLOBsElementGenerated(element, introspectedTable);
    }

    private void addLimit(TopLevelClass topLevelClass, IntrospectedTable introspectedTable, String name) {
        CommentGenerator commentGenerator = context.getCommentGenerator();
        Field field = new Field();
        field.setVisibility(JavaVisibility.PROTECTED);
        field.setType(FullyQualifiedJavaType.getIntInstance());
        field.setName(name);
        field.setInitializationString("-1");
        commentGenerator.addFieldComment(field, introspectedTable);
        topLevelClass.addField(field);
        char c = name.charAt(0);
        String camel = Character.toUpperCase(c) + name.substring(1);
        Method method = new Method();
        method.setVisibility(JavaVisibility.PUBLIC);
        method.setName("set" + camel);
        method.addParameter(new Parameter(FullyQualifiedJavaType.getIntInstance(), name));
        method.addBodyLine("this." + name + "=" + name + ";");
        commentGenerator.addGeneralMethodComment(method, introspectedTable);
        topLevelClass.addMethod(method);
        method = new Method();
        method.setVisibility(JavaVisibility.PUBLIC);
        method.setReturnType(FullyQualifiedJavaType.getIntInstance());
        method.setName("get" + camel);
        method.addBodyLine("return " + name + ";");
        commentGenerator.addGeneralMethodComment(method, introspectedTable);
        topLevelClass.addMethod(method);
    }

    private void addLimitMethod(TopLevelClass topLevelClass, IntrospectedTable introspectedTable) {
        CommentGenerator commentGenerator = context.getCommentGenerator();
        Method method = new Method();
        method.setVisibility(JavaVisibility.PUBLIC);
        method.setName("limit");
        method.addParameter(new Parameter(FullyQualifiedJavaType.getIntInstance(), "startIndex"));
        method.addParameter(new Parameter(FullyQualifiedJavaType.getIntInstance(), "pageSize"));
        method.addBodyLine("this.startIndex = startIndex;");
        method.addBodyLine("this.pageSize = pageSize;");
        commentGenerator.addGeneralMethodComment(method, introspectedTable);
        topLevelClass.addMethod(method);
    }

    /**
     * This plugin is always valid - no properties are required
     */
    @Override
    public boolean validate(List<String> warnings) {
        return true;
    }

}

使用：

直接在generator.xml文件中添加插件引用即可：

<plugin type="org.mybatis.generator.plugins.MySQLPaginationPlugin" /> <!-- 分页插件 -->