Mybatis-Plus条件构造器condition

Mybatis-Plus，在条件构造方法里，都会重载一个condition参数；

这个参数的作用是动态判断条件，假如condition是true，则拼接加条件，false的话，则不拼接加条件；

查看源码：

//
// Source code recreated from a .class file by IntelliJ IDEA
// (powered by Fernflower decompiler)
//

package com.baomidou.mybatisplus.core.conditions.interfaces;

import java.io.Serializable;
import java.util.Map;
import java.util.function.BiPredicate;

public interface Compare<Children, R> extends Serializable {
    default <V> Children allEq(Map<R, V> params) {
        return this.allEq(params, true);
    }

    default <V> Children allEq(Map<R, V> params, boolean null2IsNull) {
        return this.allEq(true, params, null2IsNull);
    }

    <V> Children allEq(boolean condition, Map<R, V> params, boolean null2IsNull);

    default <V> Children allEq(BiPredicate<R, V> filter, Map<R, V> params) {
        return this.allEq(filter, params, true);
    }

    default <V> Children allEq(BiPredicate<R, V> filter, Map<R, V> params, boolean null2IsNull) {
        return this.allEq(true, filter, params, null2IsNull);
    }

    <V> Children allEq(boolean condition, BiPredicate<R, V> filter, Map<R, V> params, boolean null2IsNull);

    default Children eq(R column, Object val) {
        return this.eq(true, column, val);
    }

    Children eq(boolean condition, R column, Object val);

    default Children ne(R column, Object val) {
        return this.ne(true, column, val);
    }

    Children ne(boolean condition, R column, Object val);

    default Children gt(R column, Object val) {
        return this.gt(true, column, val);
    }

    Children gt(boolean condition, R column, Object val);

    default Children ge(R column, Object val) {
        return this.ge(true, column, val);
    }

    Children ge(boolean condition, R column, Object val);

    default Children lt(R column, Object val) {
        return this.lt(true, column, val);
    }

    Children lt(boolean condition, R column, Object val);

    default Children le(R column, Object val) {
        return this.le(true, column, val);
    }

    Children le(boolean condition, R column, Object val);

    default Children between(R column, Object val1, Object val2) {
        return this.between(true, column, val1, val2);
    }

    Children between(boolean condition, R column, Object val1, Object val2);

    default Children notBetween(R column, Object val1, Object val2) {
        return this.notBetween(true, column, val1, val2);
    }

    Children notBetween(boolean condition, R column, Object val1, Object val2);

    default Children like(R column, Object val) {
        return this.like(true, column, val);
    }

    Children like(boolean condition, R column, Object val);

    default Children notLike(R column, Object val) {
        return this.notLike(true, column, val);
    }

    Children notLike(boolean condition, R column, Object val);

    default Children likeLeft(R column, Object val) {
        return this.likeLeft(true, column, val);
    }

    Children likeLeft(boolean condition, R column, Object val);

    default Children likeRight(R column, Object val) {
        return this.likeRight(true, column, val);
    }

    Children likeRight(boolean condition, R column, Object val);
}

如条件构造器大于有两个方法，可以看到一个是默认方法，一个多了一个参数codition,这个参数的作用是动态判断条件，如果是true，则拼接加条件，false的话，则不拼接加条件

default Children gt(R column, Object val) {
  return this.gt(true, column, val);
}

Children gt(boolean condition, R column, Object val);