lodsve.mybatis.utils.format.SqlFormatter Maven / Gradle / Ivy
/*
* Copyright (C) 2018 Sun.Hao
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see BEGIN_CLAUSES = new HashSet<>();
private static final Set END_CLAUSES = new HashSet<>();
private static final Set LOGICAL = new HashSet<>();
private static final Set QUANTIFIERS = new HashSet<>();
private static final Set DML = new HashSet<>();
private static final Set MISC = new HashSet<>();
private static final String INDENT_STRING = " ";
private static final String INITIAL = "\n ";
static {
BEGIN_CLAUSES.add("left");
BEGIN_CLAUSES.add("right");
BEGIN_CLAUSES.add("inner");
BEGIN_CLAUSES.add("outer");
BEGIN_CLAUSES.add("group");
BEGIN_CLAUSES.add("order");
END_CLAUSES.add("where");
END_CLAUSES.add("set");
END_CLAUSES.add("having");
END_CLAUSES.add("join");
END_CLAUSES.add("from");
END_CLAUSES.add("by");
END_CLAUSES.add("join");
END_CLAUSES.add("into");
END_CLAUSES.add("union");
LOGICAL.add("and");
LOGICAL.add("or");
LOGICAL.add("when");
LOGICAL.add("else");
LOGICAL.add("end");
QUANTIFIERS.add("in");
QUANTIFIERS.add("all");
QUANTIFIERS.add("exists");
QUANTIFIERS.add("some");
QUANTIFIERS.add("any");
DML.add("insert");
DML.add("update");
DML.add("delete");
MISC.add("select");
MISC.add("on");
}
public String format(String source) {
return new FormatProcess(source).perform();
}
private static class FormatProcess {
boolean beginLine = true;
boolean afterBeginBeforeEnd;
boolean afterByOrSetOrFromOrSelect;
boolean afterOn;
boolean afterBetween;
boolean afterInsert;
int inFunction;
int parensSinceSelect;
int indent = 1;
StringBuilder result = new StringBuilder();
StringTokenizer tokens;
String lastToken;
String token;
String lcToken;
private LinkedList parenCounts = new LinkedList<>();
private LinkedList afterByOrFromOrSelects = new LinkedList<>();
FormatProcess(String sql) {
tokens = new StringTokenizer(sql, "()+*/-=<>'`\"[]," + WHITESPACE, true);
}
private static boolean isFunctionName(String tok) {
final char begin = tok.charAt(0);
final boolean isIdentifier = Character.isJavaIdentifierStart(begin) || '"' == begin;
return isIdentifier && !LOGICAL.contains(tok) && !END_CLAUSES.contains(tok) && !QUANTIFIERS.contains(tok)
&& !DML.contains(tok) && !MISC.contains(tok);
}
private static boolean isWhitespace(String token) {
return WHITESPACE.contains(token);
}
String perform() {
result.append(INITIAL);
while (tokens.hasMoreTokens()) {
token = tokens.nextToken();
lcToken = token.toLowerCase(Locale.ROOT);
if ("'".equals(token)) {
String t;
do {
t = tokens.nextToken();
token += t;
}
// cannot handle single quotes
while (!"'".equals(t) && tokens.hasMoreTokens());
} else if ("\"".equals(token)) {
String t;
do {
t = tokens.nextToken();
token += t;
} while (!"\"".equals(t));
}
if (afterByOrSetOrFromOrSelect && ",".equals(token)) {
commaAfterByOrFromOrSelect();
} else if (afterOn && ",".equals(token)) {
commaAfterOn();
} else if ("(".equals(token)) {
openParen();
} else if (")".equals(token)) {
closeParen();
} else if (BEGIN_CLAUSES.contains(lcToken)) {
beginNewClause();
} else if (END_CLAUSES.contains(lcToken)) {
endNewClause();
} else if ("select".equals(lcToken)) {
select();
} else if (DML.contains(lcToken)) {
updateOrInsertOrDelete();
} else if ("values".equals(lcToken)) {
values();
} else if ("on".equals(lcToken)) {
on();
} else if (afterBetween && "and".equals(lcToken)) {
misc();
afterBetween = false;
} else if (LOGICAL.contains(lcToken)) {
logical();
} else if (isWhitespace(token)) {
white();
} else {
misc();
}
if (!isWhitespace(token)) {
lastToken = lcToken;
}
}
return result.toString();
}
private void commaAfterOn() {
out();
indent--;
newline();
afterOn = false;
afterByOrSetOrFromOrSelect = true;
}
private void commaAfterByOrFromOrSelect() {
out();
newline();
}
private void logical() {
if ("end".equals(lcToken)) {
indent--;
}
newline();
out();
beginLine = false;
}
private void on() {
indent++;
afterOn = true;
newline();
out();
beginLine = false;
}
private void misc() {
out();
if ("between".equals(lcToken)) {
afterBetween = true;
}
if (afterInsert) {
newline();
afterInsert = false;
} else {
beginLine = false;
if ("case".equals(lcToken)) {
indent++;
}
}
}
private void white() {
if (!beginLine) {
result.append(" ");
}
}
private void updateOrInsertOrDelete() {
out();
indent++;
beginLine = false;
if ("update".equals(lcToken)) {
newline();
}
if ("insert".equals(lcToken)) {
afterInsert = true;
}
}
private void select() {
out();
indent++;
newline();
parenCounts.addLast(parensSinceSelect);
afterByOrFromOrSelects.addLast(afterByOrSetOrFromOrSelect);
parensSinceSelect = 0;
afterByOrSetOrFromOrSelect = true;
}
private void out() {
result.append(token);
}
private void endNewClause() {
if (!afterBeginBeforeEnd) {
indent--;
if (afterOn) {
indent--;
afterOn = false;
}
newline();
}
out();
if (!"union".equals(lcToken)) {
indent++;
}
newline();
afterBeginBeforeEnd = false;
afterByOrSetOrFromOrSelect = "by".equals(lcToken) || "set".equals(lcToken) || "from".equals(lcToken);
}
private void beginNewClause() {
if (!afterBeginBeforeEnd) {
if (afterOn) {
indent--;
afterOn = false;
}
indent--;
newline();
}
out();
beginLine = false;
afterBeginBeforeEnd = true;
}
private void values() {
indent--;
newline();
out();
indent++;
newline();
}
private void closeParen() {
parensSinceSelect--;
if (parensSinceSelect < 0) {
indent--;
parensSinceSelect = parenCounts.removeLast();
afterByOrSetOrFromOrSelect = afterByOrFromOrSelects.removeLast();
}
if (inFunction > 0) {
inFunction--;
out();
} else {
if (!afterByOrSetOrFromOrSelect) {
indent--;
newline();
}
out();
}
beginLine = false;
}
private void openParen() {
if (isFunctionName(lastToken) || inFunction > 0) {
inFunction++;
}
beginLine = false;
if (inFunction > 0) {
out();
} else {
out();
if (!afterByOrSetOrFromOrSelect) {
indent++;
newline();
beginLine = true;
}
}
parensSinceSelect++;
}
private void newline() {
result.append("\n");
for (int i = 0; i < indent; i++) {
result.append(INDENT_STRING);
}
beginLine = true;
}
}
}