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Finding diff between two lists and adding plus and minus a more efficient way

I have two lists with with the same data except the first list might have slightly different wording.
I am making sure the fields dont match. If they dont, then i add a plus to the first word in the array and a minus to the second word in the second array.
I am just iterating over the list and i have a ton of ifs. There are other data points i will need to do also and the ifs can get very long. Is there a more efficient way of doing this?
I am not good with java 8+ and streams. Would it be better to do it with streams and if so how would i do this? Could you please do an example?
Thank you in advance!!! I really need help but i am expecting to get my heart broken!
List<ExteriorColor> f1 = vinResponseOne.getResult().getExteriorColors();
List<ExteriorColor> f2 = vinResponseTwo.getResult().getExteriorColors();
first = vinResponseOne.getResult().getExteriorColors();
second = vinResponseTwo.getResult().getExteriorColors();
private void compareExteriorColors(List<ExteriorColor> f1, List<ExteriorColor> f2){
for(int i =0; i< f1.size(); i++) {
if (!f1.get(i).getDescription().equals(f2.get(i).getDescription())) {
final String added = "+ " + f1.get(i).getDescription();
final String original = "- " + f2.get(i).getDescription();
first.get(i).setDescription(added);
second.get(i).setDescription(original);
}
if (!f1.get(i).getGenericDesc().equals(f2.get(i).getGenericDesc())) {
final String added = "+ " + f1.get(i).getGenericDesc();
final String original = "- " + f2.get(i).getGenericDesc();
first.get(i).setGenericDesc(added);
second.get(i).setGenericDesc(original);
}
if (!f1.get(i).getColorCode().equals(f2.get(i).getColorCode())) {
final String added = "+ " + f1.get(i).getColorCode();
final String original = "- " + f2.get(i).getColorCode();
f1.get(i).setColorCode(added);
f2.get(i).setColorCode(original);
}
if (f1.get(i).getInstallCause() != null) {
if (!f1.get(i).getInstallCause().equals(f2.get(i).getInstallCause())) {
final String added = "+ " + f1.get(i).getInstallCause();
final String original = "- " + f2.get(i).getInstallCause();
first.get(i).setInstallCause(added);
second.get(i).setInstallCause(original);
}
}
if (!f1.get(i).getPrimary().equals(f2.get(i).getPrimary())) {
final String added = "+ " + f1.get(i).getPrimary();
final String original = "- " + f2.get(i).getPrimary();
first.get(i).setPrimary(added);
second.get(i).setPrimary(original);
}
if (!f1.get(i).getRgbValue().equals(f2.get(i).getRgbValue())) {
final String added = "+ " + f1.get(i).getRgbValue();
final String original = "- " + f2.get(i).getRgbValue();
first.get(i).setRgbValue(added);
second.get(i).setRgbValue(original);
}
if (!f1.get(i).getStyles().equals(f2.get(i).getStyles())) {
List<String> styleFirst = new ArrayList<>();
List<String> styleSecond = new ArrayList<>();
final String added = "+ " + f1.get(i).getStyles();
final String original = "- " + f2.get(i).getStyles();
styleFirst.add(added);
styleSecond.add(original);
first.get(i).setStyles(styleFirst);
second.get(i).setStyles(styleSecond);
}
if (!f1.get(i).getType().equals(f2.get(i).getType())) {
String added = "+ " + f1.get(i).getType();
String original = "- " + f2.get(i).getType();
first.get(i).setType(added);
second.get(i).setType(original);
}
}
}
What it ends up looking like.
I will later convert to json.

class User { //Considering a simple class with only 2 fields for brevity
private String userName;
private String password;
User(String userName, String password) {
this.userName = userName;
this.password = password;
}
public String getUserName() {
return userName;
}
public void setUserName(String userName) {
this.userName = userName;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
#Override
public String toString() {
return "User{" + "userName='" + userName + '\'' + ", password='" + password + '\'' + '}';
}
}
public class S14 {
public static void main(String[] args) {
User user1 = new User("Anees", "pwd");
User user2 = new User("Anees1", "pwd");
List<User> userList1 = new ArrayList<>(Arrays.asList(user1, user2));
User user3 = new User("Anees2", "pwd");
User user4 = new User("Anees3", "pwd");
List<User> userList2 = new ArrayList<>(Arrays.asList(user3, user4));
// Assuming both Lists are of same size
IntStream.range(0, userList1.size())
.forEach(
i -> {
User firstListUser = userList1.get(i);
User secondListUser = userList2.get(i);
//HERE GOES THE MAIN PART
compareStringsAndProcessElement(
firstListUser::getUserName,
secondListUser::getUserName,
(s, s2) -> !s.equals(s2),
firstListUser::setUserName,
secondListUser::setUserName);
compareStringsAndProcessElement(
firstListUser::getPassword,
secondListUser::getPassword,
(s, s2) -> !s.equals(s2),
firstListUser::setPassword,
secondListUser::setPassword);
//AND SO ON!
});
System.out.println(userList1);
System.out.println(userList2);
}
private static void compareStringsAndProcessElement(
Supplier<String> element1,
Supplier<String> element2,
BiPredicate<String, String> stringStringBiPredicate,
Consumer<String> u1,
Consumer<String> u2) {
String e1 = element1.get();
String e2 = element2.get();
if (stringStringBiPredicate.test(e1, e2)) {
e1 = "+" + e1;
e2 = "-" + e2;
u1.accept(e1);
u2.accept(e2);
}
}
}
Hope this helps! This has nothing fancy with Streams, but uses Functional approach for a problem instead of your declarative one. This could be written with Normal loops too instead of IntStream.
PS: As far as performance goes, this might be even slower than declarative implementation since it involves multiple method calls. But, saving off some nanoseconds is not a good trade-off than code maintainability.

Java: Why does my toString method print wrong information?

I have an abstract superclass that has two attributes: int and string. I have overridden the toString method in it as well as in its subclass that has one extra attribute (LocalDate). However, for some reason that I don't understand, when I print the subclass toSring info, the int value changes.
This is what I have in the superclass:
public abstract class File {
private int id;
private String text;
public File(int newId, String newText) throws IllegalArgumentException {
id(newId);
text(newText);
}
public int id() {
return id;
}
public void id(int e) throws IllegalArgumentException {
if (e <= 0) {
throw new IllegalArgumentException();
}
else {
id = e;
}
}
public String text() {
return text;
}
public void text(String aText) throws IllegalArgumentException {
if (aText == null || aText.length() == 0) {
throw new IllegalArgumentException();
}
else {
text = aText;
}
}
#Override
public String toString() {
return '"' + id() + " - " + text() + '"';
}
Then in the subclass I have this:
public class DatedFile extends File {
private LocalDate date;
public DatedFile (int newId, LocalDate newDate, String newText) throws IllegalArgumentException {
super(newId, newText);
date(newDate);
}
public LocalDate date() {
return date;
}
public void date(LocalDate aDate) throws IllegalArgumentException {
if (aDate == null) {
throw new IllegalArgumentException();
}
else {
date = aDate;
}
}
#Override
public String toString() {
return '"' + id() + " - " + date + " - " + text() + '"';
}
I tested it like this:
public static void main(String[] args) {
LocalDate when = LocalDate.of(2020, 1, 1);
DatedFile datedFile1 = new DatedFile(999, when, "Insert text here");
System.out.println(datedFile1);
It printed: "1033 - 2020-01-01 - Insert text here"
However, if i use the following code
System.out.println(datedFile1.id());
it prints the correct id (999). So I assume that something with the toString messes it up, but I have no idea where the problem is.
PS. I'm a beginner and I'm sorry if I included too much code but as I don't know what is the problem, I really don't know what is relevant and what isn't.

Your problem is here:
return '"' + id() + " - " + date + " - " + text() + '"';
id() returns an int, and '"' is a char, which is a numeric type. So '"' + 999 is 1033, not "999.
To fix the problem, use a String instead of a character:
return "\"" + id() + " - " + date + " - " + text() + "\"";

Change your toString() method from '"' to " \"".
'"' is a character (which is stored internally as an Integer), so adding it with id() produces the result you're seeing.

or using string interpolation:
return '\" ${id()} - ${date} - ${text()} \"';

java string toString with condition

I have to write a PhonePlan object that will represent the type of plan that a customer has for his/her phone. So the object must keep track of the minutesAllowed (int), minutes used (int), dataAllowed (int), data used (int) and planType (boolean):
public class PhonePlan {
int minutesAllowed;
int minutesUsed;
int dataAllowed;
int dataUsed;
boolean planType;
}
I needed to write a constructor which has minutesAllowed, dataAllowed, and the planType as arguments which I did:
public PhonePlan (int ma, int da, boolean pt){
this.minutesAllowed = ma;
this.planType = pt;
this.dataAllowed = da;
}
And finally I have to write a string method that displays the plan depending on the type of plan.
I also have to test my code with the following test program;
public class PlanTestProgram {
public static void main(String args[]) {
System.out.println(new PhonePlan(200, 2500000, false));
System.out.println(new PhonePlan(250, 500000, true));
System.out.println(new PhonePlan(300, 5000000, false));
System.out.println(new PhonePlan(60, 1000000, false));
System.out.println(new PhonePlan(30, 0, true));
}
The first element being the minutesAllowed, the second one being the amount of dataAllowed and the third one is stating if planType is true of false.
I tried many different things but I am not able to construct a toString() method that take into account if my planType is either true or false...
My Attempt:
public String toString(){
return ( "Regular(" + minutesAllowed + " minute," + dataAllowed
+ "GB data) Monthly Plan with "
+ getMinutesRemaining() + " minutes remaining and "
+ getDataRemaining() + "KB remaining");
}

You can easily update return in your suggested (attempt) toString method, by using the shorthand if/else, into the following:
return ("Regular(" + minutesAllowed + " minute," + dataAllowed
+ "GB data) " + ((PlanType)? "Monthly": "Annual") + " Plan with "
+ getMinutesRemaining() + " minutes remaining and "
+ getDataRemaining() + "KB remaining");

Metod toString() should never be used to showcase the value of the object properties. For the overrides you can use commons library
public String toString() {
return new ToStringBuilder(this).
append("minutesAllowed", minutesAllowed).
append("minutesUsed", minutesUsed).
append("dataAllowed", dataAllowed).
append("dataUsed", dataUsed).
append("planType", planType).
toString();
}

you could implement the toString method as described in the following code
public class PhonePlan {
int minutesAllowed;
int minutesUsed;
int dataAllowed;
int dataUsed;
boolean planType;
public PhonePlan (int ma, int da, boolean pt){
this.minutesAllowed = ma;
this.planType = pt;
this.dataAllowed = da;
}
#Override
public String toString() {
return planType ? getPlanTypeBasedString("Weekly Plan") : getPlanTypeBasedString("Monthly Plan");
}
public String getPlanTypeBasedString(String planType){
return ( "Regular(" + minutesAllowed + " minute," + dataAllowed
+ "GB data) "+planType+" with "
+ getMinutesRemaining() + " minutes remaining and "
+ getDataRemaining() + "KB remaining");
}

Specifically writing from an array of courses to a csv file

I'm having trouble using a method from a class that I have written. The following method was added to a class I created named Course. The goal is to write all of the properties of the object on one line as a String.
// method to return properties as a CSV string on one line
public String toCSVString(Course c) {
String record = c.campus + ","
+ c.course + ","
+ c.section + ","
+ c.crn + ","
+ c.credits + ","
+ c.time + ","
+ c.days + "\n";
return record;
} //end toCSVString()
OK, so after adding that method to the Class. I then began to create a method (which is called from the main method) needed to write from a Course array to a CSV File which calls the above method. This is the method I wrote.
// add a method here to write from an array of courses to a CSV file
public static void writeCSV(Course[] courseArray, int count) throws Exception {
//create a File class object and give the file the name employees.csv
java.io.File courseCSV = new java.io.File("courses.csv");
//Create a Printwriter text output stream and link it to the CSV File
java.io.PrintWriter outfile = new java.io.PrintWriter(courseCSV);
//Iterate the elements actually being used
for (int i=0; i < count ; i++) {
outfile.write(courseArray.toCSVString(courseArray[i]));
}//end for
outfile.close();
} //end writeCSV()
I'm having trouble with the line that starts with "outfile.write"
In my code, I am having trouble getting Netbeans to locate the toCSVString method which is defined after the toString method in the Course class. Originally that line in the code looked like this:
outfile.write(toCSVString(courseArray[i]));
But my IDE could not find it so I added the instance of the course object in front of it. However, I am still having trouble.
Does anybody see what I am doing wrong?
EDIT #1
Here is the Course class in my program. I am having issues with the toCSVString method.
class Course implements Serializable {
private String campus; // the campus on which the course is offered
private String course; // the course number, such as CSCI 111
private String section; // the section number
private String crn; // the CRN for this section
private int credits; // the number od credits for the course
private String time; // the time the course is offered, such as 8:00 to 10:00 A.M.
private String days; // the Days the course is offered, suhc as MW
// constructors
Course() {
}
Course(String course, String section, String crn, int credits) {
this.course = course;
this.section = section;
this.crn = crn;
this.credits = credits;
} // end Course() initalizing
// muatator methods
public void setCampus(String cmp) {
this.campus = cmp;
}// end setCampus()
public void setCourse(String crse) {
this.course = crse;
}// end setCourse()
public void setSection(String sect) {
this.section = sect;
} // end setSection()
public void setCRN(String crn) {
this.crn = crn;
} // end setCRN()
public void setCredits(int cr) {
this.credits = cr;
} // end setCredits()
public void setTime(String tm) {
this.time = tm;
}// end setTime()
public void setDays(String days) {
this.days = days;
}// end setDays()
// accessor methods
public String getCampus() {
return campus;
} // end getCampus()
public String getCourse() {
return course;
} // end Course()
public String getSection() {
return section;
} // end getSection()
public String getCRN() {
return crn;
} // end getCRN()
public int getCredits() {
return credits;
} // end getCredits()
public String getTime() {
return time;
} // end getTime()
public String getDays() {
return days;
} // end getDays()
// method to compare by CRN using the String class compareTo()
public int compareTo(Course other) {
return this.crn.compareTo(other.getCRN());
} // end compareTO()
// method to return properties as a string
public String toString() {
return campus + " "
+ course + " "
+ section + " "
+ crn + " "
+ credits + " "
+ time + " "
+ days;
} // end toString()
// method to return properties as a CSV string on one line
//public String toCSVString(Course c){
public String toCSVString (Course c){
String record = campus + ","
+ course + ","
+ section + ","
+ crn + ","
+ credits + ","
+ time + ","
+ days + "\n";
return record;
} //end toCSVString()
}// end class Course

You have:
outfile.write(courseArray.toCSVString(courseArray[i]));
You mean:
outfile.write(courseArray[i].toCSVString(courseArray[i]));
As toCSVString is a member of Course, not of Course[] (courseArray is a Course[] and you are attempting to call .toCSVString() on the array itself, which is not valid).
Also note that in this form, it is redundant to pass the Course as a parameter, as you are not using it and you also would want this instead of some other Course anyways. I recommend either ditching that parameter entirely (since it is unused):
public String toCSVString () { // <- c wasn't actually used
String record = campus + "," // <- and this. is implied here
+ course + ","
+ section + ","
+ crn + ","
+ credits + ","
+ time + ","
+ days + "\n";
return record;
}
And you simply call it as:
outfile.write(courseArray[i].toCSVString());
Or, if you prefer you can make the method static and use the parameter (although that does not get you any particular benefit in this situation):
public static String toCSVString (Course c) {
String record = c.campus + ","
+ c.course + ","
+ c.section + ","
+ c.crn + ","
+ c.credits + ","
+ c.time + ","
+ c.days + "\n";
return record;
}
If you choose the static approach then you call it as:
outfile.write(Course.toCSVString(courseArray[i]));

Java Statement Pattern Matching

I am trying to write a simple template engine to parse if statements.
<{if $value == true}>
say hello
<{/if}>
I have written working code However, If I have multiple if statements in the file I am parsing then if grabs only the first and last if statement. For example.
<{if $value1 == true}>
say hello
<{/if}>
...
<{if $value2 == true}>
say hello
<{/if}>
...
The code parses and returns:
say hello
<{/if}>
...
<{if $value2 == true}>
say hello
Rather than just returning say hello.
Thanks for your help In advance the code is as follows:
public class Templates {
private static String escape(String value) {
return value.replaceAll("\\$", "\\\\\\$");
}
public static String load(String name) {
return load(name, null);
}
public static String load(String name, Map<String, String> parse) {
String page = new Resources().getTextResource("lib/tpl/" + name);
if (page == null) {
return "The template, " + name + " was NOT FOUND.";
}
if (parse != null) {
Iterator it = parse.entrySet().iterator();
while (it.hasNext()) {
Map.Entry entry = (Map.Entry) it.next();
String key = (String) entry.getKey();
String value = (String) entry.getValue();
value = escape(value); // Prevents java exception. Can't deal with $
page = page.replaceAll("\\<\\{\\$" + key + "\\}\\>", value);
}
Pattern ptrn = Pattern.compile("\\<\\{if \\$([a-z]+)\\s*(==|!=|eq|neq|or|and)\\s*(\\w+)\\}\\>(\\p{ASCII}+)\\<\\{/if\\}\\>");
Matcher mtch = ptrn.matcher(page);
System.out.println("\n\n\n");
while(mtch.find()) {
System.out.println("Key is: " + mtch.group(1));
//System.out.println("Key: " + dateMatcher.group(2));
System.out.println("Value is: " + mtch.group(3));
System.out.println("Data is: " + mtch.group(4));
if(parse.get(mtch.group(1)).equals(mtch.group(3))) {
System.out.println("\n\n\nREPLACE");
page = page.replaceAll(ptrn.pattern(), escape(mtch.group(4)));
} else {
//dateMatcher.appendReplacement(page, "");
System.out.println("\n\n\nREMOVE - " + ptrn.pattern());
page = page.replaceAll(ptrn.pattern(), "");
}
}
System.out.println("\n\n\n");
}
return page;
}
}

This might be due to greedy nature.
Try this,
(\\p{ASCII}+?) instead of (\\p{ASCII}+)