Hibernate格式化SQL源码分析

ゞ浴缸里的玫瑰 2022-11-11 13:29 191阅读 0赞

> Spring Boot 中使用 H2 数据库：[https://blog.csdn.net/qq\_40794973/article/details/106354143][https_blog.csdn.net_qq_40794973_article_details_106354143]

> [https://www.runoob.com/w3cnote/java-stringtokenizer-intro.html][https_www.runoob.com_w3cnote_java-stringtokenizer-intro.html]

>  *  org.hibernate.engine.jdbc.spi.SqlStatementLogger\#logStatement(java.lang.String, org.hibernate.engine.jdbc.internal.Formatter)
>  *  org.hibernate.engine.jdbc.internal.StatementPreparerImpl.StatementPreparationTemplate\#prepareStatement

public class StringHelper {
        public static final String WHITESPACE = " \n\r\f\t";
    }

public interface Formatter {
        String format(String source);
    }

import java.util.*;
    public class BasicFormatterImpl implements Formatter {
        private static final Set<String> BEGIN_CLAUSES = new HashSet<>();
        private static final Set<String> END_CLAUSES = new HashSet<>();
        private static final Set<String> LOGICAL = new HashSet<>();
        private static final Set<String> QUANTIFIERS = new HashSet<>();
        private static final Set<String> DML = new HashSet<>();
        private static final Set<String> MISC = new HashSet<>();
        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("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");
        }
        private static final String INDENT_STRING = "    ";
        private static final String INITIAL = "\n    ";
        @Override
        public String format(String source) {
            return new FormatProcess(source).perform();
        }
        private static class FormatProcess {
            boolean beginLine = true;
            boolean afterBeginBeforeEnd;
            boolean afterByOrSetOrFromOrSelect;
            boolean afterValues;
            boolean afterOn;
            boolean afterBetween;
            boolean afterInsert;
            int inFunction;
            int parensSinceSelect;
            private LinkedList<Integer> parenCounts = new LinkedList<>();
            private LinkedList<Boolean> afterByOrFromOrSelects = new LinkedList<>();
            /**
             *
             */
            int indent = 0;
            StringBuilder result = new StringBuilder();
            StringTokenizer tokens;
            String lastToken;
            String token;
            String lcToken;
            public FormatProcess(String sql) {
                tokens = new StringTokenizer(
                        sql,
                        "()+*/-=<>'`\"[]," + StringHelper.WHITESPACE,
                        true
                );
            }
            public String perform() {
                //result.append(INITIAL);
                result.append("\n");
                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 && lcToken.equals("and")) {
                        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();
                afterValues = true;
            }
            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 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 StringHelper.WHITESPACE.contains(token);
            }
            private void newline() {
                result.append("\n");
                for (int i = 0; i < indent; i++) {
                    result.append(INDENT_STRING);
                }
                beginLine = true;
            }
        }
    }

public class FormatterTest {
        @Test
        public void test_format() {
            String sql = "select * from user WHERE username = 'li si' and password = '123456' and age = 20";
            BasicFormatterImpl formatter = new BasicFormatterImpl();
            String formatSql = formatter.format(sql.toLowerCase());
            System.out.println("formatSql => " + formatSql);
        }
        @Test
        public void test_StringTokenizer(){
            String str = "1:2-3:4:5-6:789";
            StringTokenizer stringTokenizer = new StringTokenizer(str, ":-", true);
            while (stringTokenizer.hasMoreTokens()) {
                System.out.println(stringTokenizer.nextToken());
            }
        }
        @Test
        public void test_StringTokenizer_2() {
            String sql = "select * from user WHERE username = 'lisi' and password = '123456' and age = 20";
            StringTokenizer tokens = new StringTokenizer(
                    sql,
                    "()+*/-=<>'`\"[]," + StringHelper.WHITESPACE,
                    true
            );
            while (tokens.hasMoreTokens()) {
                System.out.println(tokens.nextToken());
            }
        }
    }

> [https://www.chendd.cn/information/viewInformation/workUsed/104.a][https_www.chendd.cn_information_viewInformation_workUsed_104.a]

[https_blog.csdn.net_qq_40794973_article_details_106354143]: https://blog.csdn.net/qq_40794973/article/details/106354143
[https_www.runoob.com_w3cnote_java-stringtokenizer-intro.html]: https://www.runoob.com/w3cnote/java-stringtokenizer-intro.html
[https_www.chendd.cn_information_viewInformation_workUsed_104.a]: https://www.chendd.cn/information/viewInformation/workUsed/104.a