46 lines
1.3 KiB
Java
46 lines
1.3 KiB
Java
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/**
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*
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*/
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package com.baeldung.string;
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/**
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* @author swpraman
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*
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*/
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public class AppendCharAtPositionX {
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public String addCharUsingCharArray(String str, char ch, int position) {
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validate(str, position);
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int len = str.length();
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char[] updatedArr = new char[len + 1];
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str.getChars(0, position, updatedArr, 0);
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updatedArr[position] = ch;
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str.getChars(position, len, updatedArr, position + 1);
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return new String(updatedArr);
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}
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public String addCharUsingSubstring(String str, char ch, int position) {
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validate(str, position);
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return str.substring(0, position) + ch + str.substring(position);
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}
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public String addCharUsingStringBuilder(String str, char ch, int position) {
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validate(str, position);
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StringBuilder sb = new StringBuilder(str);
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sb.insert(position, ch);
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return sb.toString();
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}
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private void validate(String str, int position) {
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if (str == null) {
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throw new IllegalArgumentException("Str should not be null");
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}
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int len = str.length();
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if (position < 0 || position > len) {
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throw new IllegalArgumentException("position[" + position + "] should be "
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+ "in the range 0.." + len + " for string " + str);
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}
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}
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}
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