LibJson
LibJson sample test
(For java supported modules) This program is a JSON parser.
Test files
This sample program contains several files and the source files can be found under the /src directory.
Java LibJson Test Sample Application
The libJson Test sample application can be found here: LibJson.zip
Basic usage
Compile, load and run program using java environment.
Sample of JsonArray.java file:
package com.digi.json;
import java.text.ParseException;
import java.util.LinkedList;
import java.util.List;
public class JsonArray {
private List<Object> _objects = new LinkedList<Object>();
public JsonArray() {
}
public JsonArray(String string) throws ParseException {
JsonTokenizer tokenizer = new JsonTokenizer(string);
fromTokenizer(tokenizer);
}
public JsonArray(JsonTokenizer tokenizer) throws ParseException {
fromTokenizer(tokenizer);
}
private void fromTokenizer(JsonTokenizer tokenizer) throws ParseException {
if (!tokenizer.isNextTokenStartArray()) {
throw new ParseException("Not an array!", -1);
}
// pop the open brace
tokenizer.nextToken();
// check for empty array
if (tokenizer.isNextTokenFinishArray()) {
tokenizer.nextToken();
return;
}
while (true) {
_objects.add(tokenizer.parseValue());
// if not comma, then it should've been a ']'
if (!tokenizer.nextToken().equals(",")) {
break;
}
}
}
public int size() {
return _objects.size();
}
public Object get(int index) {
return _objects.get(index);
}
public Object get(String path) {
List<String> dir = JsonTokenizer.parsePath(path);
return get(dir);
}
protected Object get(List<String> directions) {
if (directions.size() == 0)
return this;
String value = directions.remove(0);
value = value.replace("[", "");
value = value.replace("]", "");
int item = Integer.parseInt(value);
Object obj = _objects.get(item);
if (obj instanceof JsonObject) {
return ((JsonObject) obj).get(directions);
}
else if (obj instanceof JsonArray) {
return ((JsonArray) obj).get(directions);
}
return obj;
}
public String getString(int index) {
return (String) get(index);
}
public JsonObject getJsonObject(int index) {
return (JsonObject) get(index);
}
public JsonArray getJsonArray(int index) {
return (JsonArray) get(index);
}
public int getInt(int index) {
return Integer.parseInt(getString(index));
}
public long getLong(int index) {
return Long.parseLong(getString(index));
}
public float getFloat(int index) {
return Float.parseFloat(getString(index));
}
public double getDouble(int index) {
return Double.parseDouble(getString(index));
}
public Object set(int index, Object value) {
while (index >= _objects.size())
_objects.add(null);
return _objects.set(index, value);
}
protected void set(List<String> directions, Object value) throws ParseException {
if (directions.size() == 0)
throw new ParseException("Invalid path", 0);
String item = directions.remove(0);
item = item.replaceAll("\\[", "");
item = item.replaceAll("\\]", "");
int index = Integer.parseInt(item);
if (directions.size() == 0) {
set(index, value);
}
else {
// already exists
if (_objects.size() > index) {
Object obj = _objects.get(index);
if (obj instanceof JsonObject) {
JsonObject jo = (JsonObject) obj;
jo.put(directions, value);
return;
}
else if (obj instanceof JsonArray) {
JsonArray ja = (JsonArray) obj;
String child = directions.get(0);
if (child.equals("[]"))
ja.add(directions, value);
else
ja.set(directions, value);
return;
}
}
else {
String child = directions.get(0);
if (child.startsWith("[") && child.endsWith("]")) {
JsonArray ja = new JsonArray();
set(index, ja);
if (child.equals("[]"))
ja.add(directions, value);
else
ja.set(directions, value);
return;
}
else {
JsonObject jo = new JsonObject();
set(index, jo);
jo.put(directions, value);
return;
}
}
}
}
public boolean add(Object value) {
return _objects.add(value);
}
public void add(int index, Object value) {
_objects.add(index, value);
}
protected void add(List<String> directions, Object value) throws ParseException {
if (directions.size() == 0)
throw new ParseException("Invalid path", 0);
String item = directions.remove(0);
if (!item.equals("[]"))
throw new ParseException("This should never happen!", 0);
if (directions.size() == 0) {
add(value);
}
else {
String child = directions.get(0);
if (child.startsWith("[") && child.endsWith("]")) {
JsonArray ja = new JsonArray();
_objects.add(ja);
if (child.equals("[]"))
ja.add(directions, value);
else
ja.set(directions, value);
return;
}
else {
JsonObject jo = new JsonObject();
_objects.add(jo);
jo.put(directions, value);
return;
}
}
}
public Object remove(int index) {
return _objects.remove(index);
}
protected Object remove(List<String> directions) throws ParseException {
if (directions.size() == 0)
throw new ParseException("Invalid path!", -1);
String item = directions.remove(0);
item = item.replaceAll("\\[", "");
item = item.replaceAll("\\]", "");
int index = Integer.parseInt(item);
if (directions.size() == 0) {
return remove(index);
}
else {
Object obj = get(index);
if (obj instanceof JsonObject) {
JsonObject jo = (JsonObject) obj;
return jo.remove(directions);
}
else if (obj instanceof JsonArray) {
JsonArray jo = (JsonArray) obj;
return jo.remove(directions);
}
}
return null;
}
public void clear() {
_objects.clear();
}
public String display() {
return display(0).toString();
}
protected StringBuilder display(int depth) {
StringBuilder sb = new StringBuilder();
sb.append("[\n");
for (int i = 0; i < _objects.size(); i++) {
Object obj = _objects.get(i);
sb.append(JsonTokenizer.repeat(" ", depth + 1));
if (obj == null) {
sb.append("null");
}
else if (obj instanceof JsonObject) {
sb.append(((JsonObject) obj).display(depth + 1));
}
else if (obj instanceof JsonArray) {
sb.append(((JsonArray) obj).display(depth + 1));
}
else if (obj instanceof String) {
sb.append(JsonTokenizer.escapeString((String) obj));
}
else {
sb.append(obj + "");
}
if (i < _objects.size() - 1) {
sb.append(",");
}
sb.append("\n");
}
sb.append(JsonTokenizer.repeat(" ", depth));
sb.append("]");
return sb;
}
public StringBuilder toStringBuilder() {
StringBuilder sb = new StringBuilder();
sb.append("[");
for (int i = 0; i < _objects.size(); i++) {
Object obj = _objects.get(i);
if (obj == null) {
sb.append("null");
}
else if (obj instanceof JsonObject) {
sb.append(((JsonObject) obj).toStringBuilder());
}
else if (obj instanceof JsonArray) {
sb.append(((JsonArray) obj).toStringBuilder());
}
else if (obj instanceof String) {
sb.append(JsonTokenizer.escapeString((String) obj));
}
else {
sb.append(obj + "");
}
if (i < _objects.size() - 1) {
sb.append(",");
}
}
sb.append("]");
return sb;
}
public boolean has(int index) {
if (index < _objects.size())
return true;
return false;
}
protected boolean has(List<String> directions) throws ParseException {
if (directions.size() == 0)
throw new ParseException("Invalid path!", -1);
String item = directions.remove(0);
item = item.replaceAll("\\[", "");
item = item.replaceAll("\\]", "");
int index = Integer.parseInt(item);
if (!has(index))
return false;
else if (directions.size() == 0)
return true;
Object obj = get(index);
if (obj instanceof JsonObject) {
JsonObject jo = (JsonObject) obj;
return jo.has(directions);
}
else if (obj instanceof JsonArray) {
JsonArray ja = (JsonArray) obj;
return ja.has(directions);
}
return false;
}
@Override
public String toString() {
return toStringBuilder().toString();
}
}
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