I have this type of JSON:
{
"stampi":
[
{
"nome": "Ovale Piccolo 18.2x13.5cm",
"lunghezza": 18.2,
"larghezza": 13.5,
"altezza": 4,
"volume": 786.83
},
{
"nome": "Ovale Grande 22.5x17.4cm",
"lunghezza": 22.5,
"larghezza": 17.4,
"altezza": 4,
"volume": 1246.54
}
]
}
and normally I read with this code:
StringBuffer sb = new StringBuffer();
BufferedReader br = null;
try {
br = new BufferedReader(new InputStreamReader(getAssets().open("stampi.json")));
String temp;
while ((temp = br.readLine()) != null)
sb.append(temp);
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
br.close(); // stop reading
} catch (IOException e) {
e.printStackTrace();
}
}
myjson_stampi = sb.toString();
and after use the array inside the program.
I have create a menu that add new value inside the JSON file but i have a problem ...this is the code:
StringBuffer sb = new StringBuffer();
BufferedReader br = null;
try {
br = new BufferedReader(new InputStreamReader(getAssets().open("stampi.json")));
String temp;
while ((temp = br.readLine()) != null)
sb.append(temp);
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
br.close(); // stop reading
} catch (IOException e) {
e.printStackTrace();
}
}
myjson_stampi = sb.toString();
try {
// Creating JSONObject from String
JSONObject jsonObjMain = new JSONObject(myjson_stampi);
// Creating JSONArray from JSONObject
JSONArray objNames = jsonObjMain.names();
System.out.println(objNames.toString());
jsonArray_stampi = jsonObjMain.getJSONArray("stampi");
int num_elem = jsonArray_stampi.length();
jsonObjMain.put( "nome","prova");
jsonObjMain.put( "lunghezza",22);
jsonObjMain.put( "larghezza", 10);
jsonObjMain.put( "altezza", 4);
jsonObjMain.put( "volume", 10.5);
jsonArray_stampi.put( jsonObjMain );
try {
FileWriter file = new FileWriter("c:\\test.json");
//file.write(jsonArray_stampi.);
file.write( JSON.stringify(jsonArray_stampi) );
file.flush();
file.close();
} catch (IOException e) {
e.printStackTrace();
}
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
} });
why can't work correctly?
the num_elem variable are 2 always..help me!
thx Andrea
You have to create a new JSONObject and then add new data to it and then append to the existing object.
JSONObject jsonObjMain = new JSONObject(myjson_stampi); //Your existing object
JSONObject jO = new JSONObject(); //new Json Object
JSONArray jsonArray_stampi = jsonObjMain.getJSONArray("stampi"); //Array where you wish to append
//Add data
jO.put( "nome","prova");
jO.put( "lunghezza",22);
jO.put( "larghezza", 10);
jO.put( "altezza", 4);
jO.put( "volume", 10.5);
//Append
jsonArray_stampi.put(jO);
Also you should write back the complete jsonObject back to the file.
file.write(JSON.stringify(jsonObjMain));
Looks like you're trying to write to a file called c:\\test.json. Try using the proper Android way to write to files with openFileOutput. Examples are here.
String filename = "myfile";
String string = "Hello world!";
FileOutputStream outputStream;
try {
outputStream = openFileOutput(filename, Context.MODE_PRIVATE);
outputStream.write(string.getBytes());
outputStream.close();
} catch (Exception e) {
e.printStackTrace();
}
Related
I have JSON file in assets and I'm trying to read it in my MainActivity method:
private static List<JSONObject> getJSONArray(Context context) {
JSONArray myJSONarr=new JSONArray();
try
{
AssetManager am = context.getAssets();
InputStream is = am.open("chineesecardsdata.json");
String resultJson = is.toString();
is.close();
Log.d("mainActLog","file read ok: "+resultJson);
try {
}
catch (JSONException e)
{
}
}
catch(
IOException e)
{
Log.d("mainActLog","file read fail");
}
}
In log I have:
file read ok:
android.content.res.AssetManager$AssetInputStream#b123fb4
public String loadJSONFromAsset( Context context ) {
String json = null;
try {
InputStream is = context.getAssets().open("yourfilename.json");
int size = is.available();
byte[] buffer = new byte[size];
is.read(buffer);
is.close();
json = new String(buffer, "UTF-8");
} catch (IOException ex) {
ex.printStackTrace();
return null;
}
return json;
}
parse JSON
try {
JSONObject obj = new JSONObject(loadJSONFromAsset());
JSONArray array = new JSONArray(loadJSONFromAsset());
}
} catch (JSONException e) {
e.printStackTrace();
}
I am trying to save this boolean array. When I read the array the string array (parts) says that
parts[0]=true;
,but when I use Boolean.parseBoolean array[0] is still false. Can someone help me and tell me what I am doing wrong. Please and Thank You.
public void writeArraytofile() {
try {
OutputStreamWriter outputStreamWriter = new OutputStreamWriter(openFileOutput("array.txt", Context.MODE_PRIVATE));
outputStreamWriter.write(Arrays.toString(array));
outputStreamWriter.close();
} catch (IOException e) {
Log.v("MyActivity", e.toString());
}
}
public boolean[] read(){
String result = "";
boolean[] array = new boolean[2];
try {
InputStream inputStream = openFileInput("array.txt");
if (inputStream != null) {
InputStreamReader inputStreamReader = new InputStreamReader(inputStream);
BufferedReader bufferedReader = new BufferedReader(inputStreamReader);
String tempString = "";
StringBuilder stringBuilder = new StringBuilder();
while ((tempString = bufferedReader.readLine()) != null) {
stringBuilder.append(tempString);
}
inputStream.close();
result = stringBuilder.toString();
String[] parts = result.split(" ");
for (int i = 0; i < array.length; i++){
array[i]=Boolean.parseBoolean(parts[i]);
}
}
} catch (FileNotFoundException e) {
Log.v("MyActivity", "File not found" + e.toString());
} catch (IOException e) {
e.printStackTrace();
} catch (NumberFormatException e) {
//here you catch and watch the problem
Log.e("MyActivity", "cant parse string: " + result);
}
return array;
}
Arrays.toString() will print brackets and commas, so when you read the string back in and call .split(" "), the first piece will be "[true,". Since that is not just "true", Boolean.parseBoolean() will return false.
I have been working on this for a while and I am about to pull my hair out!!
If I use this...
public void readFile() {
BufferedReader buffReader = null;
StringBuilder result = new StringBuilder();
try {
FileInputStream fileIn = openFileInput("VariableStore.txt");
buffReader = new BufferedReader(new InputStreamReader(fileIn));
String line;
while ((line = buffReader.readLine()) != null) {
result.append(line);
}
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
assert buffReader != null;
buffReader.close();
} catch (IOException e) {
e.printStackTrace();
}
}
String resultString = result.toString();
String[] controlString = resultString.split("$");
// String wb = controlString[4];
// String sb = controlString[5];
((Button) this.findViewById(R.id.wakeButton)).setText(resultString);
// ((Button) this.findViewById(R.id.sleepButton)).setText(sb);
// ((Button)this.findViewById(R.id.wakeButton)).setText(result);
// ((Button)this.findViewById(R.id.wakeButton)).setText(result);
// ((Button)this.findViewById(R.id.wakeButton)).setText(result);
}
The Button.setText works fine with "resultString" or with "result" which is a string I have input formatted as xxx$xxx$xxx$xxx$xxx so when I read it back in with the readFile() I want to use .Split and put it into an array "controlString" and then assign the array elements to my widgets i.e. setText(controlString[0]); but if I so much as even uncomment the lines String wb = controlString[4]; or String sb = controlString[5]; my program crashes. Why wont the array elemts work here?
Here is my writeFile().... (Which works perfectly.
public void writeFile() {
BufferedWriter buffWriter = null;
String wb = ((Button)this.findViewById(R.id.wakeButton)).getText().toString();
String sb = ((Button)this.findViewById(R.id.sleepButton)).getText().toString();
String tb = ((EditText)this.findViewById(R.id.textHoursBetween)).getText().toString();
String ti = ((EditText)this.findViewById(R.id.textIncrementTime)).getText().toString();
String td = ((EditText)this.findViewById(R.id.textIncrementDays)).getText().toString();
String writeString = wb + "$" + sb + "$" + tb + "$" + ti + "$" + td;
try {
FileOutputStream fileOut = openFileOutput("VariableStore.txt", Context.MODE_PRIVATE);
buffWriter = new BufferedWriter(new OutputStreamWriter(fileOut));
try {
buffWriter.write(writeString);
} catch (IOException e) {
e.printStackTrace();
}
} catch (FileNotFoundException e) {
e.printStackTrace();
}finally {
try {
assert buffWriter != null;
buffWriter.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
I found the problem...
Instead of this:
String[] controlString = resultString.split("$");
I had to use this:
String[] controlString = resultString.split(Pattern.quote("$"));
I am facing one problem in StringBuffer concatination for appending large characters of String from JSONArray.
My data is huge and it is coming in log after iteration of 205 indexes of Array properly
but when I am appending each row String in StringBuffer or StringBuilder from JSONArray, so it is taking on 4063 characters only not appending all characters present in JSON Array but iteration doesn't break and goes till complete 204 rows.
String outputFinal = null;
try {
StringBuilder cryptedString = new StringBuilder(1000000);
JSONObject object = new JSONObject(response);
JSONArray serverCustArr = object.getJSONArray("ServerData");
Log.d("TAG", "SurverCust Arr "+serverCustArr.length());
for (int i = 0; i < serverCustArr.length(); i++) {
String loclCryptStr = serverCustArr.getString(i);
Log.d("TAG", "Loop Count : "+i);
cryptedString.append(loclCryptStr);
}
Log.d("TAG", "Output :"+cryptedString.toString());
CryptLib _crypt = new CryptLib();
String key = this.preference.getEncryptionKey();
String iv = this.preference.getEncryptionIV();
outputFinal = _crypt.decrypt(cryptedString.toString(), key,iv); //decrypt
System.out.println("decrypted text=" + outputFinal);
} catch (Exception e) {
e.printStackTrace();
}
My JSONArray contacts 119797 characters in 205 and after iteration for appending in StringBuffer, I have to decrypt it with library that takes string for decryption. But StringBuffer is not having complete data of 119797 characters.
And Exception is because string is not complete, I am enclosing files on link below for reference and also using cross platform CryptLib uses AES 256 for encryption easily find on Github
3 Files With Original and Logged text
Dont use StringBuffer , instead use StringBuilder ..here's the detailed Explaination
http://stackoverflow.com/questions/11908665/max-size-for-string-buffer
Hope this helps. :)
EDIT
this is the code that i used to read whole string ...
public void parseLongString(String sourceFile, String path) {
String sourceString = "";
try {
BufferedReader br = new BufferedReader(new FileReader(sourceFile));
// use this for getting Keys Listing as Input
StringBuilder sb = new StringBuilder();
String line = br.readLine();
while (line != null) {
sb.append(line);
line = br.readLine();
}
br.close();
sourceString = sb.toString();
sourceString = sourceString.toUpperCase();
System.out.println(sourceString.length());
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
File file = new File(path);
FileWriter fileWriter = null;
BufferedWriter bufferFileWriter = null;
try {
fileWriter = new FileWriter(file, true);
bufferFileWriter = new BufferedWriter(fileWriter);
} catch (IOException e1) {
System.out.println(" IOException");
e1.printStackTrace();
}
try {
fileWriter.append(sourceString);
bufferFileWriter.close();
fileWriter.close();
} catch (IOException e) {
System.out.println("IOException");
e.printStackTrace();
}
}
and this is outPut file where i am just converting it to uppercase .
https://www.dropbox.com/s/yecq0wfeao672hu/RealTextCypher%20copy_replaced.txt?dl=0
hope this helps!
EDIT 2
If u are still looking for something ..you can also try STRINGWRITER
syntax would be
StringWriter writer = new StringWriter();
try {
IOUtils.copy(request.getInputStream(), writer, "UTF-8");
} catch (IOException e2) {
// TODO Auto-generated catch block
e2.printStackTrace();
}
String theString = writer.toString();
I am using the code below to read the the txt files from my SD card, but how can I display it as Text View?
try{
File f = new File(Environment.getExternalStorageDirectory()+"/filename.txt");
FileInputStream fileIS = new FileInputStream(f);
BufferedReader buf = new BufferedReader(new InputStreamReader(fileIS));
String readString = new String();
//just reading each line and pass it on the debugger
while((readString = buf.readLine())!= null){
Log.d("line: ", readString);
}
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e){
e.printStackTrace();
}
This should do it :
public void displayOutput()
{
File sdcard = Environment.getExternalStorageDirectory();
File file = new File(sdcard,"/TextFile.txt");
StringBuilder text = new StringBuilder();
try {
BufferedReader br = new BufferedReader(new FileReader(file));
String line;
while ((line = br.readLine()) != null) {
text.append(line);
text.append('\n');
}
}
catch (IOException e) {
Toast.makeText(getApplicationContext(),"Error reading file!",Toast.LENGTH_LONG).show();
e.printStackTrace();
}
catch (FileNotFoundException e) {
Toast.makeText(getApplicationContext(),"File not found!",Toast.LENGTH_LONG).show();
e.printStackTrace();
}
TextView output=(TextView) findViewById(R.id.output);
// Assuming that 'output' is the id of your TextView
output.setText(text);
}
LinearLayout myVerticalLinearLayout = (LinearLayout) findViewById(R.id.myLinearLayout);
TextView text = new TextView(getApplicationContext());
text.setText(readString);
myVerticalLinearLayout.addView(text);
That should add vertical text views in a linear layout you should have created before.
public String readText(){
//this is your text
StringBuilder text = new StringBuilder();
try{
File f = new File(Environment.getExternalStorageDirectory()+"/filename.txt");
FileInputStream fileIS = new FileInputStream(f);
BufferedReader buf = new BufferedReader(new InputStreamReader(fileIS));
String readString = "";
//just reading each line and pass it on the debugger
while((readString = buf.readLine())!= null){
Log.d("line: ", readString);
text.append(readString + "\n");
}
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e){
e.printStackTrace();
}
return text.toString();
}
...
TextView tv=findViewById(.....);
tv.setText(readText());
public class ReadFileActivity extends Activity {
/** Called when the activity is first created. */
TextView text;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
text=(TextView)findViewById(R.id.textview);
text.setText(readTxt());
}
private String readTxt(){
InputStream inputStream = getResources().openRawResource(R.raw.aaa);
ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
int i;
try {
i = inputStream.read();
while (i != -1)
{
byteArrayOutputStream.write(i);
i = inputStream.read();
}
inputStream.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return byteArrayOutputStream.toString();
}
}