Develop Reference

Regex to get particular values from a string data

While executing a particular shell command am getting following output as follows and keeping this in a string variable
dat /var/france.log
exit
bluetooth_mac=45h6kuu
franceIP=testMarmiton
build_type=BFD
france_mac=F4:0E:83:35:E8:D1
seloger_mac=F4:0E:83:35:E8:D0
tdVersion=1.2
td_number=45G67j
france_mac=fjdjjjgj
logo_mac=tiuyiiy
logout
Connection to testMarmiton closed.
Disconnected channel and session
From this i have too fetch particular details like below and put htese values in a Map. How i can perform this using java.
bluetooth_mac=45h6kuu
build_type=BFD
tdVersion=1.2
seloger_mac=F4:0E:83:35:E8:D0
france_mac=fjdjjjgj
Map<String, String> details =new HashMap<String,String>();
details.put(bluetooth_mac, 45h6kuu);
details.put(build_type, BFD)
etc
etc

Solution 1
If you are using Java 8 you can use :
String fileName = "shell.txt";
try (Stream<String> stream = Files.lines(Paths.get(fileName))) {
Map<String, String> result = stream
.filter(line -> line.matches("\\w+=\\w+"))
.map(line -> line.split("="))
.collect(Collectors.toMap(a -> a[0], a -> a[1]));
} catch (IOException e) {
e.printStackTrace();
}
Outputs
{franceIP=testMarmiton, bluetooth_mac=45h6kuu, logo_mac=tiuyiiy, td_number=45G67j, france_mac=fjdjjjgj, build_type=BFD}
Solution 2
It seems that you have multiple line which have the same name, in this case I would like to group by a Map<String, List<String>> :
String fileName = "shell.txt";
try (Stream<String> stream = Files.lines(Paths.get(fileName))) {
Map<String, List<String>> result = stream
.filter(line -> line.matches("[^=]+=[^=]+")) // filter only the lines which contain one = signe
.map(line -> line.split("=")) // split with = sign
.collect(Collectors.groupingBy(e -> e[0], Collectors.mapping(e -> e[1], Collectors.toList())));
result.forEach((k, v) -> System.out.println(k + " : " + v));
} catch (IOException e) {
e.printStackTrace();
}
Outputs
franceIP : [testMarmiton]
bluetooth_mac : [45h6kuu]
logo_mac : [tiuyiiy]
td_number : [45G67j]
seloger_mac : [F4:0E:83:35:E8:D0]
france_mac : [F4:0E:83:35:E8:D1, fjdjjjgj]
tdVersion : [1.2]
build_type : [BFD]

public static void main(String[] args) {
String str="abc def \n"
+ "key=123 \n "
+ "pass=456 \n"
+ "not working";
String[] sarray=str.split("\\r?\\n");
for (String eachline : sarray) {
System.out.println("line " + " : " + eachline);
if(eachline.contains("="))
{
String[] sarray2=eachline.split("=");
System.out.println("key:" +sarray2[0] +":Value:"+ sarray2[1]);
}
}
System.out.println(""+sarray.length);
}
Use split("\r?\n") for new line splitting.

You could try:
Pattern re = Pattern.compile("^\\s*(.*)\\s*=(.*)$", Pattern.MULTILINE);
Matcher matcher = re.matcher(input);
while (matcher.find()) {
map.put(matcher.group(1), matcher.group(2));
}

Here's a complete example, extracting the value using regex-matching and building a HashMap (the appropriate map for key-value pairs). You can copy the whole program and run it yourself:
import java.util.HashMap;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class main {
public static void main(String[] args) {
String input = // Your input log
"dat /var/france.log\n" +
"\n" +
"exit\n" +
"\n" +
"root#france24:~# \n" +
"root#france24:~# dat /var/france.log\n" +
"bluetooth_mac=45h6kuu\n" +
"franceIP=testMarmiton\n" +
"build_type=BFD\n" +
"france_mac=F4:0E:83:35:E8:D1\n" +
"seloger_mac=F4:0E:83:35:E8:D0\n" +
"tdVersion=1.2\n" +
"td_number=45G67j\n" +
"france_mac=fjdjjjgj\n" +
"logo_mac=tiuyiiy\n" +
"root#france24:~# \n" +
"root#france24:~# exit\n" +
"logout\n" +
"Connection to testMarmiton closed.\n" +
"\n" +
"Disconnected channel and session";
String[] keys = {
"bluetooth_mac",
"build_type",
"tdVersion",
"seloger_mac",
"france_mac"
};
HashMap<String, String> map = new HashMap<>();
for(String key : keys){
String value = getValueOf(input, key);
if(value != null)
map.put(key, value);
}
for(String key : keys)
System.out.println(key + " = " + map.get(key));
}
public static String getValueOf(String input, String key){ //returns null if not found
String result = null;
Pattern pattern = Pattern.compile(key + "=.*+\\s");
Matcher matcher = pattern.matcher(input);
if(matcher.find()) {
result = matcher.group();
result = result.substring(result.indexOf('=') + 1, result.length() - 1);
}
return result;
}
}
Output (add more keys to the key-string if you want get more values):
bluetooth_mac = 45h6kuu
build_type = BFD
tdVersion = 1.2
seloger_mac = F4:0E:83:35:E8:D0
france_mac = F4:0E:83:35:E8:D1

Android: Get the entire array the value/key is in ArrayList<HashMap<String, String>>

I am trying to get v8 from the third array inside following arraylist
String[][] test = {
{"v1","v2","v3","v4","v5","v6","v7"},
{"v1","v2","v3","v4","v5","v6","v7"},
{"v1","v2","v3","v4","v5","v6","v7", "v8"}
};
ArrayList<String[]> test2= new ArrayList<String[]>(Arrays.asList(test));
Log.e("v1: ", "" + test2.get(0));
for (int j = 0; j <= test2.size(); j++) {
for (String[] arrays: test2) {
for (String string2 : arrays) {
if (string2.equalsIgnoreCase("v8")) {
Log.e("LOOOOOOOOOG", "" + test2.indexOf("v8")); // 3
}else {
Log.e("LOOOOOOOOOG", "Cant find it!!");
}
}
}
}
How would i do this?
I currently just get either -1 or Cant find it!!
I am trying to solve the above problem to solve the following HashMap problem.
public static void updateJSONdata() {
mEmailList = new ArrayList<HashMap<String, String>>();
JSONParser jParser = new JSONParser();
JSONObject json = jParser.getJSONFromUrl(READ_EMAILS_URL);
try {
mEmails = json.getJSONArray("info");
// looping through all emails according to the json object returned
for (int i = 0; i < mEmails.length(); i++) {
JSONObject c = mEmails.getJSONObject(i);
// gets the content of each tag
String email = c.getString(TAG_EMAIL);
String firstName = c.getString(TAG_FNAME);
String lastName = c.getString(TAG_LNAME);
String address = c.getString(TAG_ADDRESS);
String phoneNumber = c.getString(TAG_PHONE);
String city = c.getString(TAG_CITY);
String state = c.getString(TAG_STATE);
String zip = c.getString(TAG_ZIP);
// creating new HashMap
HashMap<String, String> map = new HashMap<String, String>();
map.put(TAG_EMAIL, email);
map.put(TAG_FNAME, firstName);
map.put(TAG_LNAME, lastName);
map.put(TAG_ADDRESS, address);
map.put(TAG_PHONE, phoneNumber);
map.put(TAG_CITY, city);
map.put(TAG_STATE, state);
map.put(TAG_ZIP, zip);
// adding HashList to ArrayList
mEmailList.add(map);
for (HashMap<String, String> maps : mEmailList){
for (Entry<String, String> mapEntry : maps.entrySet()){
String key = mapEntry.getKey();
String value = mapEntry.getValue();
if (value.equals(passedEmail)) {
Log.e("Is this email in the database?", value + " Is in the database!!!");
int index = map.get(key).indexOf(value);
Log.e("mEmailList: ", "" + mEmailList);
// String[] test = mEmailList.indexOf(value);
fullName = mEmailList.get(index).get(TAG_FNAME) +
" " +
mEmailList.get(index).get(TAG_LNAME);
mPhoneNumber = mEmailList.get(index).get(TAG_PHONE);
mAddress = mEmailList.get(index).get(TAG_ADDRESS) + " " +
mEmailList.get(index).get(TAG_CITY) + " " +
mEmailList.get(index).get(TAG_STATE) + " " +
mEmailList.get(index).get(TAG_ZIP);
}
}
}
}
} catch (JSONException e) {
e.printStackTrace();
}
}

It looks like you want the index within the list that contains a map that has a specific email address as one of the values. For that purpose you need to call indexOf on the list, and pass to it a Map.
Something like : mEmailList.indexOf(map).
What you are doing is searching for the index of the first occurrence of a sub-string within another String. That won't give you an index within the list.
In addition, it looks like you are mixing the code that creates the list of maps with the code that searches the list for a specific email.

You are getting -1 because of
test2.indexOf("v8")
The ArrayList test2 contains arrays String[], it doesn't containg "v8". test2, for example, contains { "v1", "v2", "v3", "v4", "v5", "v6", "v7", "v8" }, but not "v8".
Note: The methods String#indexOf() and ArrayList#indexOf() are different, so you should read their specification before using them.

Java custom implode methode like in PHP

I am trying to replicate the php function implode() in Java.
This is what I made:
private String implode(String delimiter, Map<String, String> map){
StringBuilder sb = new StringBuilder();
for(Entry<String, String> e : map.entrySet()){
sb.append(" "+delimiter+" ");
sb.append(" " + e.getKey() + " = '" + e.getValue() + "' ");
}
return sb.toString();
}
Testing:
Map<String, String> myList = new HashMap<String, String>();
myList.put("address", "something1");
myList.put("last_name", "something2");
myList.put("first_name", "something3");
update_database("dummy", myList, "");
public void update_database(String table, Map<String, String> update_list, String condition){
String query = "UPDATE " + table + " SET ";
query += implode(",", update_list) + " " + condition;
System.out.println(query);
}
Output:
UPDATE dummy SET , address = 'something' , last_name = 'something2',
first_name = 'something3'
If you worked with mysql before, you know that it's not a valid query because the string query start with ",".
How can I format my string to get a correct query?

You could try something like this:
Own Implementation
private String implode(String delimiter, Map<String, String> map){
boolean first = true;
StringBuilder sb = new StringBuilder();
for(Entry<String, String> e : map.entrySet()){
if (!first) sb.append(" "+delimiter+" ");
sb.append(" " + e.getKey() + " = '" + e.getValue() + "' ");
first = false;
}
return sb.toString();
}
StringUtils
Another solution would be to use public static String join(Collection collection, char separator)

You don't need to write this yourself. There's already a library with this functionality named guava made by google. It has a class called a Joiner. Here's an example:
Joiner joiner = Joiner.on("; ").skipNulls();
return joiner.join("Harry", null, "Ron", "Hermione");
This returns the string "Harry; Ron; Hermione". Note that all input elements are converted to strings using Object.toString() before being appended.

write key and values from map to a file

With the code below, I am trying to write the key and values of the male and female map to an existing file.
But it shows the following error.
Can somebody help me please.
ERROR# Map.Entry entry = (Map.Entry) entryIter.next();
java.util.NoSuchElementException
at java.util.LinkedHashMap$LinkedHashIterator.nextEntry(Unknown Source)
at java.util.LinkedHashMap$EntryIterator.next(Unknown Source)
at java.util.LinkedHashMap$EntryIterator.next(Unknown Source)
at test.main(test.java:83)
Code
public static void main(String[] args) {
Map<String, List<String>> MaleMap = new LinkedHashMap<String, List<String>>();
Map<String, List<String>> FemaleMap = new LinkedHashMap<String, List<String>>();
try {
Scanner scanner = new Scanner(new FileReader(".txt"));
while (scanner.hasNextLine()) {
String nextLine = scanner.nextLine();
String[] column = nextLine.split(":");
if (column[0].equals("Male") && (column.length == 4)) {
MaleMap.put(column[1],
Arrays.asList(column[2], column[3]));
} else if (column[0].equals("Female") && (column.length == 4)) {
FemaleMap.put(column[1],
Arrays.asList(column[2], column[3]));
}
}
Set<Entry<String, List<String>>> entries = MaleMap.entrySet();
Iterator<Entry<String, List<String>>> entryIter = entries.iterator();
while (entryIter.hasNext()) {
Map.Entry entry = (Map.Entry) entryIter.next();
Object key = entry.getKey(); // Get the key from the entry.
List<String> value = (List<String>) entry.getValue();
Object value1 = " ";
Object value2 = " ";
int counter = 0;
for (Object listItem : (List) value) {
Writer writer = null;
Object maleName = key;
Object maleAge = null;
Object maleID = null;
if (counter == 0) {// first pass assign value to value1
value1 = listItem;
counter++;// increment for next pass
} else if (counter == 1) {// second pass assign value to value2
value2 = listItem;
counter++;// so we dont keep re-assigning listItem for further iterations
}
}
System.out.println(key + ":" + value1 + "," + value2);
scanner.close();
Writer writer = null;
Object maleName = key;
Object maleAge = value1;
Object maleID = value2;
try {
String filename = ".txt";
FileWriter fw = new FileWriter(filename, true); // the true will append the new data
fw.write(maleAge + "." + maleID + "##;" + "\n"
+ " :class :" + maleName);// appends the string to the file
fw.close();
} catch (Exception e) {
e.printStackTrace();
}
}
Set<Entry<String, List<String>>> Fentries = FemaleMap.entrySet();
Iterator<Entry<String, List<String>>> FentryIter = Fentries.iterator();
while (FentryIter.hasNext()) {
Map.Entry entry = (Map.Entry) entryIter.next();
Object Fkey = entry.getKey(); // Get the key from the entry.
List<String> value = (List<String>) entry.getValue();
Object value1 = " ";
Object value2 = " ";
int counter = 0;
for (Object listItem : (List) value) {
Writer writer = null;
Object femaleName = Fkey;
Object femaleAge = null;
Object femaleID = null;
if (counter == 0) {// first pass assign value to value1
value1 = listItem;
counter++;// increment for next pass
} else if (counter == 1) {// second pass assign value to value2
value2 = listItem;
counter++;// so we dont keep re-assigning listItem for further iterations
}
}
System.out.println(Fkey + ":" + value1 + "," + value2);
scanner.close();
Writer writer = null;
Object femaleName = Fkey;
Object femaleAge = value1;
Object femaleID = value2;
try {
String filename = ".txt";
FileWriter fw = new FileWriter(filename, true); // the true will append the new data
fw.write("map:" + femaleName + " a :Bridge;" + "\n"
+ ":property" + femaleAge + ";" + "\n"
+ ":column" + " " + femaleID + " " + ";");// appends the string to the file
fw.close();
} catch (Exception e) {
e.printStackTrace();
}
}
}
}

Map.Entry entry = (Map.Entry) entryIter.next(); in your second loop is breaking.
After the first while loop that iterates through the males, your iterator has reached the end of the set, and will break when you try to call next().
What you actually want to do is iterate through your females.
Change the line to iterate with your FentryIter:
while (FentryIter.hasNext()) {
Map.Entry entry = (Map.Entry) FentryIter.next();
This is most likely the result of copy-paste code, and you need to be careful when doing this. I would recommend re-factoring your code since so much of it is duplicated.

Displaying the contents of a Map over iterator

I am trying to display the map i have created using the Iterator.
The code I am using is:
private void displayMap(Map<String, MyGroup> dg) {
Iterator it = dg.entrySet().iterator(); //line 1
while (it.hasNext()) {
Map.Entry pair = (Map.Entry)it.next();
System.out.println(pair.getKey() + " = " + pair.getValue());
it.remove();
}
}
Class MyGroup and it has two fields in it, named id and name.
I want to display these two values against the pair.getValue().
The problem here is Line 1 never gets executed nor it throws any exception.
Please Help.
PS: I have tried every method on this link.

Map<String, MyGroup> map = new HashMap<String, MyGroup>();
for (Map.Entry<String, MyGroup> entry : map.entrySet()) {
System.out.println("Key = " + entry.getKey() + ", Value = " + entry.getValue());
}
using iterator
Map<String, MyGroup> map = new HashMap<String, MyGroup>();
Iterator<Map.Entry<String, MyGroup>> entries = map.entrySet().iterator();
while (entries.hasNext()) {
Map.Entry<String, MyGroup> entry = entries.next();
System.out.println("Key = " + entry.getKey() + ", Value = " + entry.getValue());
}
For more iteration information see this link