Java tutorial
/* * codjo.net * * Common Apache License 2.0 */ package net.codjo.dataprocess.common.codec; import java.util.ArrayList; import java.util.List; import java.util.StringTokenizer; import org.apache.commons.lang.StringUtils; /** * */ public class ListCodec { private String separator = ","; private String openQuote = "'"; private String closeQuote = "'"; private boolean trim = false; public void setTrim(boolean trim) { this.trim = trim; } public String encode(List<String> parameters, String quoteOpenClose, String separatorParam) { this.openQuote = quoteOpenClose; this.closeQuote = quoteOpenClose; this.separator = separatorParam; return encode(parameters); } public String encode(List<String> parameters, Quote quote, String separatorParam) { this.openQuote = quote.openQuote; this.closeQuote = quote.closeQuote; this.separator = separatorParam; return encode(parameters); } public String encode(List<String> parameters) { if (parameters == null) { return ""; } StringBuilder res = new StringBuilder(); for (String parameter : parameters) { res.append(openQuote); if (trim) { res.append(parameter.trim()); } else { res.append(parameter); } res.append(closeQuote); res.append(separator); } if (!parameters.isEmpty()) { return res.toString().substring(0, res.length() - separator.length()); } else { return ""; } } public List<String> decode(String listAsString, String quoteOpenClose, String separatorParam) { this.openQuote = quoteOpenClose; this.closeQuote = quoteOpenClose; this.separator = separatorParam; return decode(listAsString); } public List<String> decode(String listAsString, Quote quote, String separatorParam) { this.openQuote = quote.openQuote; this.closeQuote = quote.closeQuote; this.separator = separatorParam; return decode(listAsString); } public List<String> decode(String listAsString) { List<String> parameters = new ArrayList<String>(); if (StringUtils.isEmpty(listAsString)) { return parameters; } StringBuilder partToken = new StringBuilder(); StringTokenizer listTokenizer = new StringTokenizer(listAsString, separator); while (listTokenizer.hasMoreTokens()) { String token = listTokenizer.nextToken(); if (proceedPartTok(parameters, partToken.toString())) { partToken = new StringBuilder(); } if (token.trim().startsWith(openQuote) && token.trim().endsWith(closeQuote)) { token = removeQuote(token.trim()); if (trim) { token = token.trim(); } parameters.add(token); } else { partToken.append(token); if (!partToken.toString().trim().endsWith(closeQuote)) { partToken.append(separator); } } } proceedPartTok(parameters, partToken.toString()); return parameters; } private boolean proceedPartTok(List<String> parameters, String partToken) { if (partToken.length() != 0) { if (partToken.trim().startsWith(openQuote) && partToken.trim().endsWith(closeQuote)) { partToken = removeQuote(partToken.trim()); if (trim) { partToken = partToken.trim(); } parameters.add(partToken); return true; } } return false; } String removeQuote(String str) { return str.substring(openQuote.length(), str.length() - closeQuote.length()); } static class Quote { private String openQuote; private String closeQuote; Quote(String openQuote, String closeQuote) { this.openQuote = openQuote; this.closeQuote = closeQuote; } } }