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java:get different parts of two similar strings

Get different parts of two similar strings
example：
1.String1="bjsqzctjjzxyxgs" String2="bjqzctjjxxzxyxgs" result:String[] s3 = {"s","xx"}
2.String1="bjssdwxxjsyxgs" String2="bjsdwxxjsyxgs" result:String[] s3 = {"s"}
3.String1="bjydcrwljskjyxgs" String2="bjydcrjswlkjyxgs" result:String[] s3 = {"wljs","jswl"}
for the example1,i make the string to the char array ,then i can get the String "sqzctjj" and "qzctjjxx",but i cant get the result like the example result {"s","xx"}.
I hope some friends can guide me out.
thanks

public static Map<String,String> getPreviousStrAndLastStr(String shortCompanyName, String shortSelectCompanyName){
char[] shortCompanyNameCharArray = (shortCompanyName).toCharArray();
char[] shortSelectCompanyNameCharArray = shortSelectCompanyName.toCharArray();
Map<String,String> map = new HashMap<String,String>();
int cirNum = 0;
int previousDifIndex = 0;
int lastDifIndex = 0;
String longSplitStr = "";
String shortSplitStr = "";
if(shortCompanyNameCharArray.length>shortSelectCompanyNameCharArray.length){
cirNum = shortSelectCompanyNameCharArray.length;
longSplitStr = shortCompanyName;
shortSplitStr = shortSelectCompanyName;
}else{
cirNum = shortCompanyNameCharArray.length;
longSplitStr = shortSelectCompanyName;
shortSplitStr = shortCompanyName;
}
for(int i=0;i<cirNum;i++){
if (shortCompanyNameCharArray[i]!=shortSelectCompanyNameCharArray[i]){
System.out.println(shortCompanyNameCharArray[i]+"--------"+shortSelectCompanyNameCharArray[i]);
previousDifIndex = i;
break;
}
}
if(previousDifIndex != 0){
for(int i=0;i<cirNum;i++){
if (shortCompanyNameCharArray[shortCompanyNameCharArray.length-i-1]!=shortSelectCompanyNameCharArray[shortSelectCompanyNameCharArray.length-i-1]){
System.out.println(shortCompanyNameCharArray[shortCompanyNameCharArray.length-i-1]+"--------"+shortSelectCompanyNameCharArray[shortSelectCompanyNameCharArray.length-i-1]);
lastDifIndex =shortSplitStr.length() - i;
break;
}
if(previousDifIndex==(cirNum-i)){
lastDifIndex = shortSplitStr.length() - i;;
break;
}
}
}
String previousStr = shortSplitStr.substring(0,previousDifIndex);
String lastStr = shortSplitStr.substring(lastDifIndex,shortSplitStr.length());
String diffStr1 = longSplitStr.replace(previousStr,"").replace(lastStr,"");
String diffStr2 = shortSplitStr.replace(previousStr,"").replace(lastStr,"");
map.put("previousStr",previousStr);
map.put("lastStr",lastStr);
map.put("diffStr1",diffStr1);
map.put("diffStr2",diffStr2);
map.put("previousDifIndex",previousDifIndex+"");
map.put("lastDifIndex",lastDifIndex+"");
return map;
}
input "bjydcrwljskjyxgs" and "bjqzctjjxxzxyxgs"
output {diffStr2=sqzctjj, previousStr=bj, diffStr1=qzctjjxx, lastDifIndex=9, lastStr=zxyxgs, previousDifIndex=2}
so i want to make the diffStr1="qzctjjxx"and the diffStr2="sqzctjj" how to be
the String[] s3 = {"s","xx"}

How to remove the quotes while converting a file from sql to tbl

Below is the code which converts the .sql file for insert statements into .tbl file. As the input file is .sql file it contains varchar(string) values inside single quotes. How can I prevent these quotes from getting in my tbl file?
Input:
INSERT INTO
post_tran(post_tran_id,tran_nr,datetime_tran_local,system_trace_audit_nr,settle_
amount_rsp,settle_tran_fee_rsp,post_tran_cust_id,prev_post_tran_id,next_post_tra
n_id,message_type,tran_postilion_originated,sink_node_name,settle_entity_id,batc
h_nr,tran_completed,tran_type,rsp_code_rsp,auth_type,auth_reason,retrieval_refer
ence_nr,settle_amount_req,settle_tran_fee_req,settle_currency_code,datetime_req,
recon_business_date,realtime_business_date,acquiring_inst_id_code) VALUES(
1,2,'2002-04-02 19:02:28','008497',4120,10, 2, 0,0,'0200', 0, 'LinkSink',
1,1,0,'01','01','00',0,'000000000102',6000,0,'840', '', '2004-02-11
12:00:00', '2004-02-11 12:00:00', '2200017000')
For example:
While processing sink_node_name, its data value should be LinkSink instead of 'LinkSink'.
public class SqlToTblCoverter {
private File source_folder = null;
private File destination_folder = null;
private String source_absolute_path = null;
private String destination_absolute_path = null;
private String absolute_file_name = null;
private String absolute_new_file_name = null;
private List<String> column_name_list = null;
private List<String> column_values_list = null;
public SqlToTblCoverter(String source_folder_name,
String destination_folder_name) {
source_folder = new File(source_folder_name);
destination_folder = new File(destination_folder_name);
source_absolute_path = source_folder.getAbsolutePath();
destination_absolute_path = destination_folder.getAbsolutePath();
column_name_list = new ArrayList<String>();
column_values_list = new ArrayList<String>();
}
public void run() throws IOException {
validateInputs();
migrateFiles();
}
private void validateInputs() {
if (source_folder.isDirectory() == false) {
System.out.println("Source must be a FOLDER");
} else if (destination_folder.isDirectory() == false) {
System.out.println("Destination must be a FOLDER");
}
}
private void migrateFiles() throws IOException {
String[] file_list = source_folder.list();
String file_name1 = file_list[0];
// System.out.println(file_name1);
String file_name2 = file_list[1];
// System.out.println(file_name2);
String f1 = migrateFileContains(file_name1);
String f2 = migrateFileContains(file_name2);
Migrator mg = new Migrator();
mg.migrate(f1, f2);
}
private String migrateFileContains(String file_name) throws IOException {
absolute_file_name = source_absolute_path + File.separator + file_name;
absolute_new_file_name = destination_absolute_path + File.separator
+ getNewFileName(file_name);
BufferedReader br = new BufferedReader(new InputStreamReader(
new FileInputStream(new File(absolute_file_name))));
String line_info = br.readLine();
StringBuffer new_query = new StringBuffer("");
FileWriter fw = new FileWriter(new File(absolute_new_file_name));
while (line_info != null) {
String convertQuery = convertQuery(line_info);
if (convertQuery.isEmpty()) {
line_info = br.readLine();
continue;
}
new_query.append(convertQuery);
new_query.append(System.getProperty("line.separator"));
fw.write(new_query.toString());
new_query.setLength(0);
line_info = br.readLine();
}
br.close();
fw.close();
return absolute_new_file_name;
}
private String convertQuery(String query) {
String new_query = "";
if (query.startsWith("INSERT")) {
int round_bracket_start = query.indexOf('(');
int round_bracket_end = query.indexOf(')');
int round_bracket_start_after_values = query.indexOf('(',
round_bracket_end);
String query_column_name = query.substring(round_bracket_start + 1,
round_bracket_end);
String query_column_values = query.substring(
round_bracket_start_after_values + 1, query.length() - 1);
covertColumnNameList(query_column_name);
covertColumnValueList(',' + query_column_values + ',');
new_query = createNewQuery() + "\n";
}
column_name_list.clear();
column_values_list.clear();
return new_query;
}
private void covertColumnNameList(String query_column_name) {
String[] column_list = query_column_name.split(",");
for (String column_name : column_list) {
column_name_list.add(column_name);
}
}
private void covertColumnValueList(String query_column_values) {
if (query_column_values.equals(",")) {
return;
}
String column_value = null;
int comma_index = query_column_values.indexOf(',');
int next_comma_index = 0;
if (query_column_values.charAt(comma_index + 1) == '\'') {
int quote_index = query_column_values.indexOf('\'', comma_index);
int next_quote_index = query_column_values.indexOf('\'',
quote_index + 1);
next_comma_index = query_column_values.indexOf(',',
next_quote_index);
column_value = query_column_values.substring(comma_index + 2,
next_comma_index - 1);
} else {
next_comma_index = query_column_values
.indexOf(',', comma_index + 1);
column_value = query_column_values.substring(comma_index + 1,
next_comma_index);
}
column_values_list.add(column_value);
covertColumnValueList(query_column_values.substring(next_comma_index));
}
private String createNewQuery() {
StringBuffer buffer = new StringBuffer("");
if (column_name_list.size() != column_values_list.size()) {
System.out.println("Error : " + absolute_file_name);
} else {
for (int index = 0; index < column_name_list.size(); index++) {
buffer.append(createNewColumn(column_name_list.get(index),
column_values_list.get(index)));
}
}
return buffer.toString();
}
private String createNewColumn(String column_name, String column_value) {
StringBuffer buffer = new StringBuffer("");
buffer.append("[name]".trim());
buffer.append(column_name.trim());
buffer.append("[/name]=[data]".trim());
buffer.append(column_value.trim());
buffer.append("[/data]".trim());
buffer.append("\r\n");
return buffer.toString();
}
private String getNewFileName(String file_name) {
String new_file_name = "";
int dot_index = file_name.indexOf('.');
new_file_name = file_name.subSequence(0, dot_index) + ".tbl";
return new_file_name;
}
}

You can replace covertColumnValueList with below code:
private void covertColumnValueList(String query_column_values) {
String temp_val = null;
for (String col_val : query_column_values.split(",")) {
if (col_val.contains("\'")) {
temp_val = col_val.replaceAll("\'", "");
column_values_list.add(temp_val.trim());
} else
column_values_list.add(col_val.trim());
}
}
I assume you have query_column_values something like below:
String query_column_values = "1,2,'2002-04-02 19:02:28','008497',4120,10, 2, 0,0,'0200', 0, 'LinkSink', 1,1,0,'01','01','00',0,'000000000102',6000,0,'840', '', '2004-02-11 12:00:00', '2004-02-11 12:00:00', '2200017000'";
replace '' by current date: Once you populate this list, replace list value at specified index.
DateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
Calendar cal = Calendar.getInstance();
column_values_list.set( 23, dateFormat.format(cal.getTime()));

The code to remove the delimiting apostrophes is there in covertColumnValueList, but it doesn't handle the case where a space precedes the apostroph. See the simple fix below.
//....
int next_comma_index = 0;
// skip space(s)
while( query_column_values.charAt(comma_index + 1) == ' ' ){
comma_index++;
}
if (query_column_values.charAt(comma_index + 1) == '\'') {
//...

private void covertColumnValueList(String query_column_values) {
if (query_column_values.equals(",")) {
return;
}
String column_value = null;
int comma_index = query_column_values.indexOf(',');
int next_comma_index = 0;
if (query_column_values.charAt(comma_index + 1) == '\'') {
int quote_index = query_column_values.indexOf('\'', comma_index);
int next_quote_index = query_column_values.indexOf('\'',
quote_index + 1);
next_comma_index = query_column_values.indexOf(',',
next_quote_index);
column_value = query_column_values.substring(comma_index + 2,
next_comma_index - 1);
column_value=column_value.replace("\'","") ;
} else {
next_comma_index = query_column_values
.indexOf(',', comma_index + 1);
column_value = query_column_values.substring(comma_index + 1,
next_comma_index);
column_value=column_value.replace("\'","") ;
}
column_values_list.add(column_value);
covertColumnValueList(query_column_values.substring(next_comma_index));
}

Need help in creating a regular expression in Java

I am trying to apply regex on a string to obtain the output in the below format.
Input string:
params=Param1{index}~[Value1|Value2|....]^Param2~[Value1|Value2|....]
Output should be in the form of Map<String,List<String>>
Eg.
Key1: Param1
Value : Value1,Value2 upto ValueN
Key2 :Param2
Value: Value1,Value2 uptoValueN
Code:
Her is the code that I am trying to do.
String textPatt = "params";
String key = textPatt.replace("/[\\[]/", "\\[").replace("/[\\]]/", "\\]");
String pattern = new String("[\\?&]" + key + "=([^&#]*)");
Pattern p = Pattern.compile(pattern);
Matcher m = p.matcher(masterUrl);
List<String> paramList = new ArrayList<String>();
if (m.find()) {
String param = m.group();
if(param != null){
String[] multiParamArr = null;
if(param.indexOf("^") != -1){
multiParamArr = param.split("\\^");
}else{
multiParamArr = new String[1];
multiParamArr[0] = param;
}
if(multiParamArr != null && multiParamArr .length > 0){
Pattern refinePattern = null;
Matcher refineMatcher = null;
String paramKeyy = null;
String paramVal = null;
HashMap<String,List<String>> ParamMap = new HashMap<String,List<String>>();
List<String list = new ArrayList<String>();
for(int i=0;i<multiParamArr.length;i++){
String[] multiParam = null;
String patternKey = "^[^\\~]*";
refinePattern = Pattern.compile(patternKey);
refineMatcher = refinePattern.matcher(multiRefineArr[i]);
if(refineMatcher.find()){
paramKey = refineMatcher.group();
if(paramKey.indexOf("=") !=-1){
patternKey = patternKey.substring(patternKey.indexOf("=")+1);
}
if(paramKey.indexOf("{") !=-1){
patternKey = patternKey.substring(patternKey.indexOf("=")+1,patternKey.indexOf("{"));
}
}
if(multiParamArr[i].indexOf("|") != -1){
multiParam = multiParamArr[i].split("\\|");
int startIndex;
int endIndex;
for(int j=0;j<multiParam.length;j++){
startIndex = 0;
endIndex = 0;
ifmultiParamArr[j].indexOf("[") > -1){
startIndex = multiParamArr[j].indexOf("[")+1;
}
ifmultiParamArr[j].indexOf("]") > -1){
endIndex = multiParamArr[j].indexOf("]");
}else{
endIndex = multiParamArr[j].length();
}
paramVal = multiParamArr[j].substring(startIndex,endIndex);
}
}else{
paramVal = multiParamArr[i].substring(multiParamArr[i].indexOfmultiParamArr[i].indexOf("]"));
}
list.add(paramVal);
}
paramMap.put((paramKey,list);
}
}
}
how to apply a single regex and achieve the output

Instead of trying to create a complex regex and maintain it, you can do it simpler and in a more readable way, in a few steps:
Split on ^
Now you have an array of Strings, each of which contains one of the parameters with its values
Split each string on ~ - you'll get an array of two strings, extract from the first the Param1 (Param2 etc)
From the second you can extract the list of values by splitting on
| (pipe).

String index out of Bounds Exception error

I am making a program to read .java files and extract all comments from it and write it to an html file. The file works mostly but i am having trouble extracting the names of each method as it confuses "Exception{" as a separate class/method.
So far this is the code i have and i believe it is almost done.
http://pastebin.com/qrbJAaW3
public class ParseDoc {
static String fileName = null;
static String outputR = "";
static String inputR = "";
static String[] lines;
static String [] classnames;
static StringBuilder classn = new StringBuilder();
static String classnam = "";
/**
* This Method asks the user for path to input and output file
* then it reads the file and places it on a string for easier sorting.
* The string is sorted line by line into an array and cleaned.
* #return Array of DOC comments
* #throws Exception
*/
public static String[] scanread() throws Exception{
System.out.println("NOTICE: If a valid file path is not entered, the program will not return a DOCHTML document.");
Scanner inputReader = new Scanner(System.in);
System.out.println("Please enter path to input file (ex: C:/Program Files/Code.java : " );
inputR = inputReader.nextLine();
System.out.println("Please enter path to html output file (ex: C:/Program Files/Output.html : " );
outputR = inputReader.nextLine();
inputReader.close();
FileReader file = new FileReader(inputR);
BufferedReader reader = new BufferedReader(file);
String line = reader.readLine();
//NAME OF THE SOURCE FILE
int index = inputR.lastIndexOf("/");
fileName = inputR.substring(index + 1);
int z = 0;
//This loop turns the input file into an String for easier access
while (line!= null){
line = reader.readLine();
z += 1;
}
reader.close();
file.close();
FileReader file2 = new FileReader(inputR);
BufferedReader reader2 = new BufferedReader(file2);
String line2 = reader2.readLine();
lines = new String[z];
int j = 0;
while(line2 != null)
{
line2 = line2.trim();
lines[j] = line2;
line2 = reader2.readLine();
j += 1;
}
reader2.close();
file2.close();
return lines;
}
/**
* Removes all the comments from the Array containing strings
* #param lines contains strings made of input file
* #return Array with removed strings
*/
public static String[] removeComments(String[] lines){
for (int i=0; i <lines.length;i++){
if (lines[i].startsWith("//"))
{
lines[i]="";
}
}
return lines;
}
/**
* This method scans the entire code for name of the classes and methods
* along with their parameters and stores them in an Array for further use
* #param lines
* #return lines array without changing any content
*/
public static String[] classNames(String[] lines)
{
int total = 0;
String[] matches = new String[] {"public ", "class ","private "};
for(int b = 0; b <lines.length;b++)
{
Matcher num = Pattern.compile("\\S+\\s*\\(([^)]*)\\)").matcher(lines[b]);
for (int n = 0; n < 3 ;n++)
{
if (lines[b].contains(matches[n]))
{
while(num.find())
{
total += 1;
}
}
}
}
classnames = new String[total];
for(int z = 0; z<lines.length;z++)
{
Matcher mzz = Pattern.compile("\\w+\\s*\\{").matcher(lines[z]);
for (int k = 0; k < 3; k++)
{
if (lines[z].contains(matches[k])&& !(lines[z].contains("throws "))) //&& !(lines[z].contains("throws "))
{
while(mzz.find())
{
classn.append( mzz.group()+"break");
}
}
}
}
for(int z = 0; z <lines.length;z++)
{
//This matcher with Regex looks for class/method names along with any parameters inside
Matcher m = Pattern.compile("\\S+\\s*\\(([^)]*)\\)").matcher(lines[z]);
int i = 0;
for (int k = 0; k < 3; k++)
{
if (lines[z].contains(matches[k]) )
{
while(m.find())
{
classn.append( m.group()+"break");
continue;
}
}
}
}
classnam = classn.toString();
classnames = classnam.split("break");
/*for(int step = 0; step<classnames.length;step++)
{
System.out.println(classnames[step]);
}*/
return lines;
}
/**
* This method removes all the code from the Array and leaves on the
* Doc comments intact.
* #param lines
* #return lines array with only comments remaining ( code is removed )
*/
public static String[] removeCode(String[] lines)
{
int rep = 0;
while ( rep <lines.length){
lines[rep] = lines[rep].replaceAll("\\*", "Z");
if(!(lines[rep].startsWith("Z") || (lines[rep].startsWith("/")))){
lines[rep]="";
}
lines[rep] = lines[rep].replaceAll("Z", "\\*");
rep += 1;
}
for(int num = 0; num <lines.length; num++)
{
if(lines[num].isEmpty()){
lines[num] = null;
}
}
return lines;
}
/**
* This method removes the remaining stars, slashes and properly formats each comment
* before printing it.
* #param lines The array contains parsed Java Doc comments
* #return
* #throws Exception
*/
public static String[] writeTo(String[] lines) throws Exception
{
BufferedWriter outputWriter = null;
outputWriter = new BufferedWriter(new FileWriter(outputR));
StringBuilder writeTo = new StringBuilder();
writeTo.append("<html>\n<body>\n<h2><mark> JAVA DOC COMMENTS</mark> </h2>\n<pre>\n"
+"<big><b>Source File:</b> </big>" +"<big>"+ fileName+"</big>" + "\n\n");
for(int step = 0; step<lines.length;step++)
{
if(!(lines[step] == null))
{
lines[step] = lines[step].replace("#author", "<b>Author: </b>\n&nbsp&nbsp&nbsp");
lines[step] = lines[step].replace("#since", "<b>Since: </b>\n&nbsp&nbsp&nbsp");
lines[step] = lines[step].replace("#version", "<b>Version: </b>\n&nbsp&nbsp&nbsp");
lines[step] = lines[step].replace("#param", "<b>Parameter: </b>\n&nbsp&nbsp&nbsp");
lines[step] = lines[step].replace("#return", "<b>Return: </b>\n&nbsp&nbsp&nbsp");
//lines[step] = lines[step].replace("*", "");
}
}
outputWriter.write(writeTo.toString());
//write to HTML
int countz = 0;
int comcount = 0;
//classnames[]
for(int resum = 0; resum<lines.length;resum++)
{
if(lines[resum] != null)
{
if( lines[resum].charAt(0) == '*' )
{
lines[resum] = lines[resum].replace("*","");
}
}
}
for(int i = 0; i < classnames.length; i++)
{
System.out.println(classnames[i]);
}
for(int resum = 0; resum<lines.length;resum++)
{
if(lines[resum] != null)
{
if( lines[resum].charAt(0) == '/' )
{
if(lines[resum].endsWith("*"))
{
lines[resum] = lines[resum].replace("/**","<b>"+classnames[countz]+"</b>");
countz++;
}
}
if( lines[resum].charAt(0) == '/' )
{
lines[resum] = lines[resum].replace("/","\n");
}
}
}
/*for(int resum = 0; resum<lines.length;resum++)
{
}*/
for(int f = 0; f<lines.length;f++)
{
if(lines[f] != null)
{
/*if(lines[f].startsWith("//") && lines[f].length() == 2)
{
lines[f] = "TEEEST";
countz++;
}*/
outputWriter.write(lines[f]+"\n");
}
}
outputWriter.close();
return null;
}
}
Console:
Please enter path to input file (ex: C:/Program Files/Code.java :
I:\ICS4U0\DocParse\src\java_doc_parse\ParseDoc.java
Please enter path to html output file (ex: C:/Program Files/Output.html :
I:\ICS4U0\DocParse\src\java_doc_parse\ParseDochh.html
ParseDoc {
scanread()
removeComments(String[] lines)
Exception in thread "main" java.lang.StringIndexOutOfBoundsException: String index out of range: 0
at java.lang.String.charAt(Unknown Source)
at java_doc_parse.ParseDoc.writeTo(ParseDoc.java:285)
at java_doc_parse.Execute.main(Execute.java:14)
classNames(String[] lines)
removeCode(String[] lines)
writeTo(String[] lines)
I am not sure what is causing this error. Is there a way to fix it or should i just give up on adding class names to comments altogether?
Sorry if i am lacking some information, but i am quite confused myself.

The error seems to be because you call charAt(0) on what appears to be an empty string.
You already have a null check above, I don't know if it's valid (can your lines ever be null?), but I would change that to a length check, possibly combined with the existing null check.
if (lines[resum] != null && lines[resum].length > 0) {

I think this is where your error resides:
for(int resum = 0; resum<lines.length;resum++)
{
if(lines[resum] != null)
{
if( lines[resum].charAt(0) == '/' )
{
if(lines[resum].endsWith("*"))
{
lines[resum] = lines[resum].replace("/**","<b>"+classnames[countz]+"</b>");
countz++;
}
}
if( lines[resum].charAt(0) == '/' )
{
lines[resum] = lines[resum].replace("/","\n");
}
}
}
Try this instead, move the null check before entering the for loop:
if(lines[0] != null)
{
for(int resum = 0; resum<lines.length;resum++)
{
if( lines[resum].charAt(0) == '/' )
{
if(lines[resum].endsWith("*"))
{
lines[resum] = lines[resum].replace("/**","<b>"+classnames[countz]+"</b>");
countz++;
}
}
if( lines[resum].charAt(0) == '/' )
{
lines[resum] = lines[resum].replace("/","\n");
}
}
}

How would I tidy this code into a loop in java?

public class TagHandler {
private final String START = "<START ";
private final String END = "<END ";
public String handleTag(String buf, String[] attrList) {
String startPattern1 = START+attrList[0]+">";
String endPattern1 = END+attrList[0]+">";
String startPattern2 = START+attrList[1]+">";
String endPattern2 = END+attrList[1]+">";
String startPattern3 = START+attrList[2]+">";
String endPattern3 = END+attrList[2]+">";
String startPattern4 = START+attrList[3]+">";
String endPattern4 = END+attrList[3]+">";
String startPattern5 = START+attrList[4]+">";
String endPattern5 = END+attrList[4]+">";
String extract1 = new String(buf);
String extract2 = new String(buf);
String extract3 = new String(buf);
String extract4 = new String(buf);
String extract5 = new String(buf);
extract1 = extract1.substring(extract1.indexOf(startPattern1)+startPattern1.length(), extract1.indexOf(endPattern1));
extract2 = extract2.substring(extract2.indexOf(startPattern2)+startPattern2.length(), extract2.indexOf(endPattern2));
extract3 = extract3.substring(extract3.indexOf(startPattern3)+startPattern3.length(), extract3.indexOf(endPattern3));
extract4 = extract4.substring(extract4.indexOf(startPattern4)+startPattern4.length(), extract4.indexOf(endPattern4));
extract5 = extract5.substring(extract5.indexOf(startPattern5)+startPattern5.length(), extract5.indexOf(endPattern5));
String s = ("BLOPABP"+extract1) + ("\nBLOPCALL"+extract2) +("\nBLOPEXP"+extract3) +("\nBLOPHEAD"+extract4)+("\nBLOPMAJ"+extract5);
return s;
}
How would I tidy up the code above into some sort of loop? Basically I have a file that i'm reading and extract the data within the tags and I'm passing the tags into this TagHandler method and returning the extracted data as a string with the tag headers without the "< START >" and "< END TAG"> leaving only the header on the start tag.

Here you go. This should do what you want.
public class TagHandler {
private final String START = "<START ";
private final String END = "<END ";
public String handleTag(String buf, String[] attrList) {
String[] blop = {"BLOPABP", "BLOPCALL", "BLOPEXP", "BLOPHEAD", "BLOPMAJ"};
String s = "";
for (int i = 0; i < attrList.length; i++) {
String startPattern = START+attrList[i]+">";
String endPattern = END+attrList[i]+">";
String extract = buf.substring(buf.indexOf(startPattern)+startPattern.length(), buf.indexOf(endPattern));
s += blop[i]+extract;
if (i < attrList.length-1) {
s += "\n";
}
}
return s;
}
}
Look out for an out of bounds exception, if attrList has more than 5 elements.

You can try something like this, optimize it if you can :
public String handleTag(String buf, String[] attrList) {
StringBuilder temp = new StringBuilder();
final String[] prefix = {"BLOPABP","\nBLOPCALL","\nBLOPEXP",
"\nBLOPHEAD","\nBLOPMAJ"};
for(int i=0;i<attrList.length;i++){
String startPattern = START+attrList[i]+">";
String endPattern = END+attrList[i]+">";
String extract = new String(buf);
extract = extract.substring(
extract.indexOf(startPattern)+startPattern.length(),
extract.indexOf(endPattern));
temp.append(prefix[i%5]+extract);
}
return temp.toString();
}

This should work. You can replace = new ArrayList<String> with = new ArrayList<>() if you're using java 7.
private final String START = "<START ";
private final String END = "<END ";
List<String> startPatterns = new ArrayList<String>();//can use ArrayList<> instead if java 1.7
List<String> stringExtracts = new ArrayList<String>();
final String[] tags = new String[]{"BLOPABP","\nBLOPCALL","\nBLOPEXP","\nBLOPHEAD","\nBLOPMAJ"};
public String handleTag(String buf, String[] attrList) {
int numPatterns = tags.length;
String s;
String extract = new String(buf);
for(int i=0; i<numPatterns; i++){
String startPattern = START+attrList[i]+">";
startPatterns.add(startPattern);
String endPattern = END+attrList[i]+">";
endPatterns.add(endPattern);
String extract = extract.substring(extract.indexOf(startPattern)+startPattern.length(), extract.indexOf(endPattern));
stringExtracts.add(extract);
s += tags[i] + extract;
}
return s;
}
This assumes that you need access to the individual startPatterns, endPatterns and stringExtracts again, not just s. If you only need s though then discard the ArrayLists - it will work like this:
private final String START = "<START ";
private final String END = "<END ";
final String[] tags = new String[]{"BLOPABP","\nBLOPCALL","\nBLOPEXP","\nBLOPHEAD","\nBLOPMAJ"};
public String handleTag(String buf, String[] attrList) {
int numPatterns = tags.length;
String s;
String extract = new String(buf);
for(int i=0; i<numPatterns; i++){
String startPattern = START+attrList[i]+">";
String endPattern = END+attrList[i]+">";
String extract = extract.substring(extract.indexOf(startPattern)+startPattern.length(), extract.indexOf(endPattern));
s += tags[i] + extract;
}
return s;
}