java/sql-dk/src/main/java/info/globalcode/sql/dk/formatting/AbstractFormatter.java
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/java/sql-dk/src/main/java/info/globalcode/sql/dk/formatting/AbstractFormatter.java Mon Mar 04 20:15:24 2019 +0100
@@ -0,0 +1,254 @@
+/**
+ * SQL-DK
+ * Copyright © 2013 František Kučera (frantovo.cz)
+ *
+ * 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 <http://www.gnu.org/licenses/>.
+ */
+package info.globalcode.sql.dk.formatting;
+
+import info.globalcode.sql.dk.Parameter;
+import info.globalcode.sql.dk.configuration.DatabaseDefinition;
+import java.util.EmptyStackException;
+import java.util.EnumSet;
+import java.util.List;
+import java.util.Stack;
+
+/**
+ * <ol>
+ * <li>ensures integrity – if methods are called in correct order and context</li>
+ * <li>provides default implmentations of methods that does not produce any output for given
+ * events</li>
+ * </ol>
+ *
+ * @author Ing. František Kučera (frantovo.cz)
+ */
+public abstract class AbstractFormatter implements Formatter {
+
+ private Stack<State> state = new Stack<>();
+ private FormatterContext formatterContext;
+ private ColumnsHeader currentColumnsHeader;
+ private String currentQuery;
+ private int currentColumnsCount;
+ private int currentRowCount;
+
+ public AbstractFormatter(FormatterContext formatterContext) {
+ this.formatterContext = formatterContext;
+ state.push(State.ROOT);
+ }
+
+ /*
+ * root
+ * .batch
+ * ..database
+ * ...statement
+ * ....@query
+ * ....@parameters
+ * ....resultSet
+ * .....row
+ * ......@columnValue
+ * ....@updatesResult
+ */
+ protected enum State {
+
+ ROOT,
+ BATCH,
+ DATABASE,
+ STATEMENT,
+ RESULT_SET,
+ ROW
+ }
+
+ /**
+ * Go down in hierarchy.
+ * Pushes new state and verifies the old one.
+ *
+ * @param current the new state – currently entering
+ * @param expected expected previous states (any of them is valid)
+ * @return previous state
+ * @throws IllegalStateException if previous state was not one from expected
+ */
+ private State pushState(State current, EnumSet expected) {
+ State previous = state.peek();
+
+ if (expected.contains(previous)) {
+ state.push(current);
+ return previous;
+ } else {
+ throw new IllegalStateException("Formatter was in wrong state: " + previous + " when it should be in one of: " + expected);
+ }
+ }
+
+ protected State peekState(EnumSet expected) {
+ State current = state.peek();
+
+ if (expected.contains(current)) {
+ return current;
+ } else {
+ throw new IllegalStateException("Formatter is in wrong state: " + current + " when it should be in one of: " + expected);
+ }
+
+ }
+
+ /**
+ * Go up in hierarchy.
+ * Pops the superior state/branch.
+ *
+ * @param expected expected superior state
+ * @return the superior state
+ * @throws IllegalStateException if superior state was not one from expected or if there is no
+ * more superior state (we are at root level)
+ */
+ private State popState(EnumSet expected) {
+ try {
+ state.pop();
+ State superior = state.peek();
+ if (expected.contains(superior)) {
+ return superior;
+ } else {
+ throw new IllegalStateException("Formatter had wrong superior state: " + superior + " when it should be in one of: " + expected);
+ }
+ } catch (EmptyStackException e) {
+ throw new IllegalStateException("Formatter was already at root level – there is nothing above that.", e);
+ }
+ }
+
+ @Override
+ public void writeStartBatch() {
+ pushState(State.BATCH, EnumSet.of(State.ROOT));
+ }
+
+ @Override
+ public void writeEndBatch() {
+ popState(EnumSet.of(State.ROOT));
+ }
+
+ @Override
+ public void writeStartDatabase(DatabaseDefinition databaseDefinition) {
+ pushState(State.DATABASE, EnumSet.of(State.BATCH));
+ }
+
+ @Override
+ public void writeEndDatabase() {
+ popState(EnumSet.of(State.BATCH));
+ }
+
+ @Override
+ public void writeStartStatement() {
+ pushState(State.STATEMENT, EnumSet.of(State.DATABASE));
+ }
+
+ @Override
+ public void writeEndStatement() {
+ popState(EnumSet.of(State.DATABASE));
+ }
+
+ @Override
+ public void writeStartResultSet(ColumnsHeader header) {
+ pushState(State.RESULT_SET, EnumSet.of(State.STATEMENT));
+ currentRowCount = 0;
+ currentColumnsHeader = header;
+ }
+
+ @Override
+ public void writeEndResultSet() {
+ popState(EnumSet.of(State.STATEMENT));
+ currentColumnsHeader = null;
+ }
+
+ @Override
+ public void writeQuery(String sql) {
+ peekState(EnumSet.of(State.STATEMENT));
+
+ if (currentColumnsHeader == null) {
+ currentQuery = sql;
+ } else {
+ throw new IllegalStateException("Query string '" + sql + "' must be set before columns header – was already set: " + currentColumnsHeader);
+ }
+ }
+
+ @Override
+ public void writeParameters(List<? extends Parameter> parameters) {
+ peekState(EnumSet.of(State.STATEMENT));
+
+ if (currentColumnsHeader != null) {
+ throw new IllegalStateException("Parameters '" + parameters + "' must be set before columns header – was already set: " + currentColumnsHeader);
+ }
+
+ if (currentQuery == null && parameters != null) {
+ throw new IllegalStateException("Parameters '" + parameters + "' must be set after query – was not yet set.");
+ }
+ }
+
+ @Override
+ public void writeStartRow() {
+ pushState(State.ROW, EnumSet.of(State.RESULT_SET));
+ currentColumnsCount = 0;
+ currentRowCount++;
+ }
+
+ @Override
+ public void writeEndRow() {
+ popState(EnumSet.of(State.RESULT_SET));
+ }
+
+ @Override
+ public void writeColumnValue(Object value) {
+ peekState(EnumSet.of(State.ROW));
+ currentColumnsCount++;
+
+ int declaredCount = currentColumnsHeader.getColumnCount();
+ if (currentColumnsCount > declaredCount) {
+ throw new IllegalStateException("Current columns count is " + currentColumnsCount + " which is more than declared " + declaredCount + " in header.");
+ }
+ }
+
+ @Override
+ public void writeUpdatesResult(int updatedRowsCount) {
+ peekState(EnumSet.of(State.STATEMENT));
+ }
+
+ @Override
+ public void close() throws FormatterException {
+ }
+
+ public FormatterContext getFormatterContext() {
+ return formatterContext;
+ }
+
+ protected ColumnsHeader getCurrentColumnsHeader() {
+ return currentColumnsHeader;
+ }
+
+ /**
+ * @return column number, 1 = first
+ */
+ protected int getCurrentColumnsCount() {
+ return currentColumnsCount;
+ }
+
+ protected boolean isCurrentColumnFirst() {
+ return currentColumnsCount == 1;
+ }
+
+ protected boolean isCurrentColumnLast() {
+ return currentColumnsCount == currentColumnsHeader.getColumnCount();
+ }
+
+ /**
+ * @return row number, 1 = first
+ */
+ protected int getCurrentRowCount() {
+ return currentRowCount;
+ }
+}