SQL Node 1.05版

输出:

select
    a.f1,
    b.f2
from
    table01 a,
    (
        select
            a
        from
            tb
    )
    b
where
    a.f1=1 and
    b.f2=2 or
    b.f3=3
order by
    a.f1,
    b.f2

Text         Depth        Parent       Prev         Next         Child Cnt
------------------------------------------------------------------------------------
NULL         0            NULL         NULL         NULL         4
select       0            null         NULL         from         3
a.f1         1            select       NULL         ,            0
,            1            select       a.f1         b.f2         0
b.f2         1            select       ,            NULL         0
from         0            null         select       where        3
table01 a    1            from         NULL         ,            0
,            1            from         table01 a    null         0
NULL         1            from         ,            NULL         4
(            1            null         NULL         null         0
NULL         1            null         (            )            2
select       2            null         NULL         from         1
a            3            select       NULL         NULL         0
from         2            null         select       NULL         1
tb           3            from         NULL         NULL         0
)            1            null         null         b            0
b            1            null         )            NULL         0
where        0            null         from         order by     5
a.f1=1       1            where        NULL         and          0
and          1            where        a.f1=1       b.f2=2       0
b.f2=2       1            where        and          or           0
or           1            where        b.f2=2       b.f3=3       0
b.f3=3       1            where        or           NULL         0
order by     0            null         where        NULL         3
a.f1         1            order by     NULL         ,            0
,            1            order by     a.f1         b.f2         0
b.f2         1            order by     ,            NULL         0            

程序:

package com.heyang.easysql.nod05;

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

/**
 * Sql Node v1.05
 * @author Heyang
 *
 */
public class Node {
    private static final String FOUR_SPACE = "    ";
    private static final String ONE_SPACE = " ";
    private String text=null;
    private int depth=0;
    private Node parent=null;
    private Node prev=null;
    private Node next=null;
    private List<Node> children=null;
    public static final int TYPE_NORMAL=1;
    public static final int TYPE_JOINT=2;
    public static final int TYPE_TRANSPARENT=3;
    private int type=TYPE_NORMAL;

    public Node() {

    }

    public Node(int type) {
        this.type=type;
    }

    public Node(String text) {
        this.text=text;
    }

    public Node(String text,int type) {
        this.text=text;
        this.type=type;
    }

    public boolean isLeaf() {
        return children==null || children.size()==0;
    }

    private List<Node> addChild(Node child) {
        if(children==null) {
            children=new ArrayList<Node>();
        }

        if(children.size()>0) {
            Node last=children.get(children.size()-1);
            last.next=child;
            child.prev=last;
        }

        child.parent=this;
        child.depth=this.depth+(this.type==TYPE_TRANSPARENT?0:1);

        children.add(child);
        adjustDepth();

        return children;
    }

    private String getIndentSpace() {
        return String.join("", Collections.nCopies(this.depth, FOUR_SPACE));
    }

    private void adjustDepth() {
        if(children!=null) {
            for(Node child:children) {
                child.depth=this.depth+(this.type==TYPE_TRANSPARENT?0:1);
                child.adjustDepth();
            }
        }
    }

    public void printHeaders() {
        final String continuousStar = createRepeatedStr("-", 84);
        final String layout = "%-12s %-12s %-12s %-12s %-12s %-12s %s";
        StringBuilder sb = new StringBuilder();

        sb.append(String.format(layout, "Text", "Depth","Parent","Prev","Next","Child Cnt","\n"));
        sb.append(continuousStar + "\n");
        System.out.print(sb.toString());
    }

    public void printTree() {
        final String layout = "%-12s %-12s %-12s %-12s %-12s %-12s %s";
        StringBuilder sb = new StringBuilder();

        String text=(this.text==null?"NULL":this.text);
        int count=(this.children==null?0:this.children.size());
        String parentText=(this.parent==null?"NULL":this.parent.text);
        String prevText=(this.prev==null?"NULL":this.prev.text);
        String nextText=(this.next==null?"NULL":this.next.text);

        sb.append(String.format(layout, text,String.valueOf(this.depth), parentText,prevText,nextText,String.valueOf(count),"\n"));
        System.out.print(sb.toString());

        if(count>0) {
            for(Node child:children) {
                child.printTree();
            }
        }
    }

    private static String createRepeatedStr(String seed, int n) {
        return String.join("", Collections.nCopies(n, seed));
    }

    public String toString() {
        StringBuilder sb=new StringBuilder();

        final String tabs=getIndentSpace();

        if(this.text!=null) {
            if(this.type!=TYPE_JOINT) {
                sb.append(tabs+this.text);
            }else {
                if(",".equalsIgnoreCase(this.text)) {
                    sb.append(this.text);
                }else {
                    sb.append(ONE_SPACE+this.text);
                }
            }

            if(this.next!=null) {
                if(this.next.type!=TYPE_JOINT) {
                    sb.append("\n");
                }
            }else {
                sb.append("\n");
            }
        }

        if(children!=null) {
            for(Node child:children) {
                sb.append(child.toString());
            }
        }

        return sb.toString();
    }

    public static void main(String[] args) {
        Node f1=new Node("a.f1");
        Node comma=new Node(",",Node.TYPE_JOINT);
        Node f2=new Node("b.f2");

        Node select=new Node("select");
        select.addChild(f1);
        select.addChild(comma);
        select.addChild(f2);

        Node t1=new Node("table01 a");
        Node tComma=new Node(",",Node.TYPE_JOINT);

        Node childSelect=new Node("select");
        childSelect.addChild(new Node("a"));

        Node childFrom=new Node("from");
        childFrom.addChild(new Node("tb"));

        Node subSelect=new Node();
        subSelect.addChild(childSelect);
        subSelect.addChild(childFrom);

        Node t2=new Node(Node.TYPE_TRANSPARENT);
        t2.addChild(new Node("("));
        t2.addChild(subSelect);
        t2.addChild(new Node(")"));
        t2.addChild(new Node("b"));

        Node from=new Node("from");
        from.addChild(t1);
        from.addChild(tComma);
        from.addChild(t2);

        Node w1=new Node("a.f1=1");
        Node wAnd=new Node("and",Node.TYPE_JOINT);
        Node w2=new Node("b.f2=2");
        Node wor=new Node("or",Node.TYPE_JOINT);
        Node w3=new Node("b.f3=3");

        Node where=new Node("where");
        where.addChild(w1);
        where.addChild(wAnd);
        where.addChild(w2);
        where.addChild(wor);
        where.addChild(w3);

        Node orderby=new Node("order by");
        orderby.addChild(new Node("a.f1"));
        orderby.addChild(new Node(",",Node.TYPE_JOINT));
        orderby.addChild(new Node("b.f2"));

        Node query=new Node(Node.TYPE_TRANSPARENT);
        query.addChild(select);
        query.addChild(from);
        query.addChild(where);
        query.addChild(orderby);

        System.out.println(query);
        query.printHeaders();
        query.printTree();
    }
}

--2020年5月15日--