org.jspringbot.keyword.db.SQLFormatter Maven / Gradle / Ivy
package org.jspringbot.keyword.db;
import org.apache.commons.lang.StringUtils;
import java.util.HashSet;
import java.util.LinkedList;
import java.util.Set;
import java.util.StringTokenizer;
public class SQLFormatter {
public static String prettyPrint(String unformattedSQL) {
if(StringUtils.trim(unformattedSQL).length() <= 50) {
return StringUtils.trim(unformattedSQL);
}
return new SQLFormatter().format(unformattedSQL);
}
private static final Set 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();
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" );
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" );
}
static final String indentString = " ";
static final String initial = "\n";
public String format(String source) {
return new FormatProcess( source ).perform();
}
private static class FormatProcess {
private static final String WHITESPACE = " \n\r\f\t";
boolean beginLine = true;
boolean afterBeginBeforeEnd = false;
boolean afterByOrSetOrFromOrSelect = false;
boolean afterValues = false;
boolean afterOn = false;
boolean afterBetween = false;
boolean afterInsert = false;
int inFunction = 0;
int parensSinceSelect = 0;
private LinkedList parenCounts = new LinkedList();
private LinkedList afterByOrFromOrSelects = new LinkedList();
int indent = 1;
StringBuffer result = new StringBuffer();
StringTokenizer tokens;
String lastToken;
String token;
String lcToken;
public FormatProcess(String sql) {
tokens = new StringTokenizer(
sql,
"()+*/-=<>'`\"[]," + WHITESPACE,
true
);
}
public String perform() {
result.append( initial );
while ( tokens.hasMoreTokens() ) {
token = tokens.nextToken();
lcToken = token.toLowerCase();
if ( "'".equals( token ) ) {
String t;
do {
t = tokens.nextToken();
token += t;
}
while ( !"'".equals( t ) && tokens.hasMoreTokens() ); // cannot handle single quotes
}
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 WHITESPACE.contains(token);
}
private void newline() {
result.append( "\n" );
for ( int i = 0; i < indent; i++ ) {
result.append( indentString );
}
beginLine = true;
}
}
}