package com.avaje.ebeaninternal.server.deploy;
import java.util.ArrayList;
import java.util.List;
import javax.persistence.PersistenceException;
import com.avaje.ebean.config.NamingConvention;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Parses columnMapping (select clause) mapping columns to bean properties.
*/
public final class DRawSqlSelectColumnsParser {
private static final Logger logger = LoggerFactory.getLogger(DRawSqlSelectColumnsParser.class);
/**
* Description of how the match was made.
*/
private String matchDescription;
/**
* The actual column string used in search for a matching property.
* <p>
* This has table alias' and quoted identifiers removed.
* </p>
*/
private String searchColumn;
private int columnIndex;
private int pos;
private final int end;
private final String sqlSelect;
private final List<DRawSqlColumnInfo> columns = new ArrayList<DRawSqlColumnInfo>();
private final BeanDescriptor<?> desc;
private final NamingConvention namingConvention;
private final DRawSqlSelectBuilder parent;
private final boolean debug;
public DRawSqlSelectColumnsParser(DRawSqlSelectBuilder parent, String sqlSelect) {
this.parent = parent;
this.debug = parent.isDebug();
this.namingConvention = parent.getNamingConvention();
this.desc = parent.getBeanDescriptor();
this.sqlSelect = sqlSelect;
this.end = sqlSelect.length();
}
public List<DRawSqlColumnInfo> parse() {
while (pos <= end) {
nextColumnInfo();
}
return columns;
}
private void nextColumnInfo() {
int start = pos;
nextComma();
String colInfo = sqlSelect.substring(start, pos);
pos++;
colInfo = colInfo.trim();
int secLastSpace = -1;
int lastSpace = colInfo.lastIndexOf(' ');
if (lastSpace > -1) {
secLastSpace = colInfo.lastIndexOf(' ', lastSpace - 1);
}
String colName = null;
String colLabel = null;
if (lastSpace == -1) {
// no column alias
colName = colInfo;
colLabel = colName;
} else if (secLastSpace == -1) {
// no 'as' keyword
colName = colInfo.substring(0, lastSpace);
colLabel = colInfo.substring(lastSpace + 1);
if (colName.equals("")) {
colName = colLabel;
}
} else {
// check for as keyword
String expectedAs = colInfo.substring(secLastSpace + 1, lastSpace);
if (expectedAs.toLowerCase().equals("as")) {
colName = colInfo.substring(0, secLastSpace);
colLabel = colInfo.substring(lastSpace + 1);
} else {
String msg = "Error in " + parent.getErrName() + ". ";
msg += "Expected \"AS\" keyword but got [" + expectedAs + "] in select clause ["
+ colInfo + "]";
throw new PersistenceException(msg);
}
}
BeanProperty prop = findProperty(colLabel);
if (prop == null) {
if (debug) {
String msg = "ColumnMapping ... idx[" + columnIndex
+ "] ERROR, no property found to match... column[" + colName + "] label[" + colLabel
+ "] search[" + searchColumn + "]";
parent.debug(msg);
}
String msg = "Error in " + parent.getErrName() + ". ";
msg += "No matching bean property for column[" + colName + "] columnLabel[" + colLabel
+ "] idx[" + columnIndex + "] using search[" + searchColumn + "] found?";
logger.error(msg);
} else {
String msg = null;
if (debug || logger.isDebugEnabled()) {
msg = "ColumnMapping ... idx[" + columnIndex + "] match column[" + colName
+ "] label[" + colLabel + "] to property[" + prop + "]"
+ matchDescription;
}
if (debug) {
parent.debug(msg);
}
if (logger.isDebugEnabled()) {
logger.debug(msg);
}
DRawSqlColumnInfo info = new DRawSqlColumnInfo(colName, colLabel, prop.getName(), prop.isScalar());
columns.add(info);
columnIndex++;
}
}
private String removeQuotedIdentifierChars(String columnLabel) {
char c = columnLabel.charAt(0);
if (Character.isJavaIdentifierStart(c)) {
return columnLabel;
}
// trim off first and last character
String result = columnLabel.substring(1, columnLabel.length() - 1);
String msg = "sql-select trimming quoted identifier from["
+ columnLabel + "] to[" + result+ "]";
logger.debug(msg);
return result;
}
/**
* Find the property to match against the given resultSet column.
*/
private BeanProperty findProperty(String column) {
searchColumn = column;
int dotPos = searchColumn.indexOf(".");
if (dotPos > -1) {
searchColumn = searchColumn.substring(dotPos + 1);
}
searchColumn = removeQuotedIdentifierChars(searchColumn);
BeanProperty matchingProp = desc.getBeanProperty(searchColumn);
if (matchingProp != null) {
matchDescription = "";
return matchingProp;
}
// convert columnName using the namingConvention
String propertyName = namingConvention.getPropertyFromColumn(desc.getBeanType(), searchColumn);
matchingProp = desc.getBeanProperty(propertyName);
if (matchingProp != null) {
matchDescription = " ... using naming convention";
return matchingProp;
}
matchDescription = " ... by linear search";
// search all properties matching against the property db column
BeanProperty[] propertiesBase = desc.propertiesBaseScalar();
for (int i = 0; i < propertiesBase.length; i++) {
BeanProperty prop = propertiesBase[i];
if (isMatch(prop, searchColumn)) {
return prop;
}
}
BeanProperty idProp = desc.getIdProperty();
if (idProp != null) {
if (isMatch(idProp, searchColumn)) {
return idProp;
}
}
BeanPropertyAssocOne<?>[] propertiesAssocOne = desc.propertiesOne();
for (int i = 0; i < propertiesAssocOne.length; i++) {
BeanProperty prop = propertiesAssocOne[i];
if (isMatch(prop, searchColumn)) {
return prop;
}
}
return null;
}
private boolean isMatch(BeanProperty prop, String columnLabel) {
if (columnLabel.equalsIgnoreCase(prop.getDbColumn())) {
return true;
}
if (columnLabel.equalsIgnoreCase(prop.getName())) {
return true;
}
return false;
}
private int nextComma() {
boolean inQuote = false;
while (pos < end) {
char c = sqlSelect.charAt(pos);
if (c == '\'') {
inQuote = !inQuote;
} else if (!inQuote && c == ',') {
return pos;
}
pos++;
}
return pos;
}
}