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Add full-fledged in-memory parser for #14
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More tests and performance tuning come later.
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@leadpony
leadpony committed May 22, 2019
1 parent 4f6e322 commit 871d1e2
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Showing 10 changed files with 681 additions and 529 deletions.
162 changes: 11 additions & 151 deletions justify/src/main/java/org/leadpony/justify/internal/base/json/AbstractJsonParser.java
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Original file line number Diff line number Diff line change
Expand Up @@ -27,14 +27,8 @@
import java.util.stream.Stream;
import java.util.stream.StreamSupport;

import javax.json.JsonArray;
import javax.json.JsonArrayBuilder;
import javax.json.JsonBuilderFactory;
import javax.json.JsonException;
import javax.json.JsonObject;
import javax.json.JsonObjectBuilder;
import javax.json.JsonValue;
import javax.json.spi.JsonProvider;
import javax.json.stream.JsonLocation;
import javax.json.stream.JsonParser;
import javax.json.stream.JsonParsingException;
Expand All @@ -48,71 +42,9 @@
*/
abstract class AbstractJsonParser implements JsonParser {

private final JsonProvider jsonProvider;
private final JsonBuilderFactory builderFactory;
private Event currentEvent;

/**
* Constructs this parser.
*
* @param jsonProvider the JSON provider.
*/
protected AbstractJsonParser(JsonProvider jsonProvider) {
this.jsonProvider = jsonProvider;
this.builderFactory = jsonProvider.createBuilderFactory(null);
}

/* JsonParser */

@Override
public final Event next() {
Event event = fetchNextEvent();
event = process(event);
this.currentEvent = event;
postprocess();
return event;
}

@Override
public JsonArray getArray() {
if (this.currentEvent != Event.START_ARRAY) {
throw newIllegalStateException("getArray");
}
return buildArray();
}

@Override
public JsonObject getObject() {
if (this.currentEvent != Event.START_OBJECT) {
throw newIllegalStateException("getObject");
}
return buildObject();
}

@Override
public JsonValue getValue() {
switch (this.currentEvent) {
case START_ARRAY:
return buildArray();
case START_OBJECT:
return buildObject();
case VALUE_TRUE:
return JsonValue.TRUE;
case VALUE_FALSE:
return JsonValue.FALSE;
case VALUE_NULL:
return JsonValue.NULL;
case KEY_NAME:
case VALUE_STRING:
return getJsonString();
case VALUE_NUMBER:
return getJsonNumber();
case END_ARRAY:
case END_OBJECT:
default:
throw newIllegalStateException("getValue");
}
}
/* As a JsonParser */

@Override
public void skipArray() {
Expand Down Expand Up @@ -174,60 +106,22 @@ public Stream<JsonValue> getValueStream() {
return StreamSupport.stream(new JsonValueSpliterator(), false);
}

/* AbstractJsonParser */

public final JsonProvider getJsonProvider() {
return jsonProvider;
}

public final JsonBuilderFactory getJsonBuilderFactory() {
return builderFactory;
}
/* As a AbstractJsonParser */

/**
* Returns the location of the last char.
* Returns the current event.
*
* @return the location of the last char.
* @return the current event.
*/
public JsonLocation getLastCharLocation() {
return SimpleJsonLocation.before(getLocation());
}

/**
* Return the current parser event.
*
* @return the current parser event.
*/
public final Event getCurrentEvent() {
protected final Event getCurrentEvent() {
return currentEvent;
}

public JsonValue getJsonString() {
return jsonProvider.createValue(getString());
}

public JsonValue getJsonNumber() {
if (isIntegralNumber()) {
return jsonProvider.createValue(getLong());
} else {
return jsonProvider.createValue(getBigDecimal());
}
}

protected abstract Event fetchNextEvent();

/**
* Processes the currrent parser event.
*
* @param event the current parser event.
* @return the event to be delivered to the client.
*/
protected Event process(Event event) {
return event;
protected final void setCurrentEvent(Event event) {
this.currentEvent = event;
}

protected void postprocess() {
}
protected abstract JsonLocation getLastCharLocation();

/**
* Checks if this parser is in array or object scope.
Expand All @@ -237,63 +131,29 @@ protected void postprocess() {
*/
protected abstract boolean isInCollection();

private JsonArray buildArray() {
JsonArrayBuilder builder = getJsonBuilderFactory().createArrayBuilder();
while (hasNext()) {
Event event = next();
if (event == Event.END_ARRAY) {
return builder.build();
}
builder.add(getValue());
}
throw newParsingException(
Event.START_OBJECT,
Event.START_ARRAY,
Event.VALUE_STRING,
Event.VALUE_NUMBER,
Event.VALUE_TRUE,
Event.VALUE_FALSE,
Event.VALUE_NULL,
Event.END_ARRAY);
}

private JsonObject buildObject() {
JsonObjectBuilder builder = getJsonBuilderFactory().createObjectBuilder();
while (hasNext()) {
Event event = next();
if (event == Event.END_OBJECT) {
return builder.build();
}
String name = getString();
next();
builder.add(name, getValue());
}
throw newParsingException(Event.KEY_NAME, Event.END_OBJECT);
}

/**
* Creates an instance of {@link IllegalStateException} for the specified
* method.
*
* @param method the name of the method.
* @return the newly created exception.
*/
protected IllegalStateException newIllegalStateException(String method) {
protected final IllegalStateException newIllegalStateException(String method) {
Map<String, Object> args = new HashMap<>();
args.put("method", method);
args.put("event", getCurrentEvent());
String message = Message.PARSER_ILLEGAL_STATE.format(args);
return new IllegalStateException(message);
}

private JsonParsingException newParsingException(Event... expected) {
protected final JsonParsingException newParsingException(Event... expected) {
Map<String, Object> args = new HashMap<>();
args.put("expected", Arrays.asList(expected));
String message = Message.PARSER_UNEXPECTED_EOI.format(args);
return new JsonParsingException(message, getLastCharLocation());
}

private JsonException newInternalError() {
protected final JsonException newInternalError() {
return new JsonException("Internal error");
}

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