Class SqlFormatter

src/main/java/com/sql/parse/util/SqlFormatter.java:12–336

@date 2019/4/30 15:06 @desc sql格式化工具

 * @desc sql格式化工具
 */
public class SqlFormatter {
    private static final Set<String> BEGIN_CLAUSES = new HashSet<String>();
    private static final Set<String> END_CLAUSES = new HashSet<String>();
    private static final Set<String> LOGICAL = new HashSet<String>();
    private static final Set<String> QUANTIFIERS = new HashSet<String>();
    private static final Set<String> DML = new HashSet<String>();
    private static final Set<String> MISC = new HashSet<String>();
    static final String indentString = "    ";
    static final String initial = "\n    ";

    public static String format(String source) {
        return new FormatProcess(source).perform().trim();
    }

    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");
        END_CLAUSES.add("limit");

        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 class FormatProcess {
        boolean beginLine = true;
        boolean afterBeginBeforeEnd = false;
        boolean afterByOrSetOrFromOrSelect = false;
        boolean afterValues = false;
        boolean afterOn = false;