android - java.lang.OutOfMemoryError on String.replace -

i have 1 text file contains 234 lines of string1@string2@string3.

kya@きゃ@キャ kyu@きゅ@キュ kyo@きょ@キョ sha@しゃ@シャ shu@しゅ@シュ ...so 234 lines 

i writing converter converts word string2 or string3 word string1.

inputstream = context.getresources().openrawresource(r.raw.kanatoromaji); inputstreamreader isr = new inputstreamreader(is); bufferedreader reader = new bufferedreader(isr); string line; try {     while ((line = reader.readline()) != null) {         string[] parts = line.split("@");         string romaji = parts[0];         string hiragana=parts[1];         string katakana = parts[2];          if (hiragana!=null&&word.contains(hiragana)) {                 word = word.replace(hiragana, romaji);//in line getting outofmemory error         }         if (word.contains(katakana)) {             word = word.replace(katakana, romaji);         }     }  } catch (ioexception e) {     e.printstacktrace(); } 

i calling method many times (200k-300k times in 1 run). causing error: 07-24 00:52:32.859 10848-10848/net.joerichard.test e/androidruntime﹕ fatal

exception: main     java.lang.outofmemoryerror             @ java.lang.abstractstringbuilder.enlargebuffer(abstractstringbuilder.java:94)             @ java.lang.abstractstringbuilder.append0(abstractstringbuilder.java:132)             @ java.lang.stringbuilder.append(stringbuilder.java:124)             @ java.lang.string.replace(string.java:1367)             @ net.joerichard.test.converter.kanatoromaji(converter.java:32)             @ net.joerichard.test.mainactivity.migratekanakanji(mainactivity.java:222)             @ net.joerichard.test.mainactivity.access$700(mainactivity.java:29)             @ net.joerichard.test.mainactivity$10.onclick(mainactivity.java:131)             @ android.view.view.performclick(view.java:4240)             @ android.view.view$performclick.run(view.java:17721)             @ android.os.handler.handlecallback(handler.java:730)             @ android.os.handler.dispatchmessage(handler.java:92)             @ android.os.looper.loop(looper.java:137)             @ android.app.activitythread.main(activitythread.java:5103)             @ java.lang.reflect.method.invokenative(native method)             @ java.lang.reflect.method.invoke(method.java:525)             @ com.android.internal.os.zygoteinit$methodandargscaller.run(zygoteinit.java:737)             @ com.android.internal.os.zygoteinit.main(zygoteinit.java:553)             @ dalvik.system.nativestart.main(native method) 

what problem in code? how solve it?

update:

according jfpicard's answer, converted string word stringbuilder sbword. tried replace string2 , string3 using stringbuilder. never replaced stringbuilder before. search in google , found solution replace stringbuilder parts. code looks this:

public static string kanatoromaji(context context, string word) {      string kana = word;     stringbuilder sbword = new stringbuilder(word);      inputstream = context.getresources().openrawresource(r.raw.kanatoromaji);     inputstreamreader isr = new inputstreamreader(is);     bufferedreader reader = new bufferedreader(isr);     string line;     try {         while ((line = reader.readline()) != null) {             string[] parts = line.split("@");             string romaji = parts[0];             string hiragana=parts[1];             string katakana = parts[2];              if (hiragana!=null&&word.contains(hiragana)) {                 sbword = replaceall(sbword, hiragana, romaji);//in line getting outofmemory error             }             if (word.contains(katakana)) {                 sbword = replaceall(sbword, katakana, romaji);             }         }      }     catch (ioexception e) {         e.printstacktrace();     }      char[] chars = kana.tochararray();     (char character: chars)     {         if(sbword.tostring().contains(string.valueof(character)))         {             new mylog(kana+":"+sbword.tostring());             break;         }     }      return word; } 

method replace stringbuilder parts:

public static stringbuilder replaceall(stringbuilder builder, string from, string to) {     int index = builder.indexof(from);     while (index != -1)     {         builder.replace(index, index + from.length(), to);         index += to.length(); // move end of replacement         index = builder.indexof(from, index);     }     return builder; } 

now getting error: 07-24 01:23:52.890 13512-13512/net.joerichard.test e/androidruntime﹕ fatal

exception: main java.lang.outofmemoryerror @ java.lang.abstractstringbuilder.move(abstractstringbuilder.java:397) @ java.lang.abstractstringbuilder.insert0(abstractstringbuilder.java:356) @ java.lang.abstractstringbuilder.replace0(abstractstringbuilder.java:442) @ java.lang.stringbuilder.replace(stringbuilder.java:637) @ net.joerichard.test.converter.replaceall(converter.java:65) @ net.joerichard.test.converter.kanatoromaji(converter.java:33) @ net.joerichard.test.mainactivity.migratekanakanji(mainactivity.java:222) @ net.joerichard.test.mainactivity.access$700(mainactivity.java:29) @ net.joerichard.test.mainactivity$10.onclick(mainactivity.java:131) @ android.view.view.performclick(view.java:4240) @ android.view.view$performclick.run(view.java:17721) @ android.os.handler.handlecallback(handler.java:730) @ android.os.handler.dispatchmessage(handler.java:92) @ android.os.looper.loop(looper.java:137) @ android.app.activitythread.main(activitythread.java:5103) @ java.lang.reflect.method.invokenative(native method) @ java.lang.reflect.method.invoke(method.java:525) @ com.android.internal.os.zygoteinit$methodandargscaller.run(zygoteinit.java:737) @ com.android.internal.os.zygoteinit.main(zygoteinit.java:553) @ dalvik.system.nativestart.main(native method)

what in situation?

i think have idea.

this line word = word.replace(hiragana, romaji);

and 1 word = word.replace(katakana, romaji);

create new string each time. string immutable consume memory. lot in case.

try use stringbuilder instead.