Java tutorial
package com.btoddb.chronicle; /* * #%L * fast-persistent-queue * %% * Copyright (C) 2014 btoddb.com * %% * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN * THE SOFTWARE. * #L% */ import org.apache.commons.lang3.builder.EqualsBuilder; import org.apache.commons.lang3.builder.HashCodeBuilder; import org.apache.commons.lang3.builder.ToStringBuilder; import org.joda.time.DateTimeZone; import org.joda.time.format.DateTimeFormat; import org.joda.time.format.DateTimeFormatter; import java.util.ArrayList; import java.util.List; /** * */ public class TokenizedFormatter { private String delimiter = ":"; private String pattern; private List<TokenizingPart> compiledPattern; public TokenizedFormatter(String pattern) { this.pattern = pattern; this.compiledPattern = compilePattern(); } public String render(Event event) { return render(event, null); } public String render(TokenValueProvider provider) { return render(null, provider); } public String render(Event event, TokenValueProvider provider) { StringBuilder sb = new StringBuilder(); for (TokenizingPart part : compiledPattern) { // if string, then just append it if (part instanceof StringPart) { sb.append(part.raw); } // if a header part, then lookup in event headers else if (null != event && part instanceof HeaderPart) { sb.append(((HeaderPart) part).render(event)); } // if key is found in headers, then use it. otherwise let it be else if (part instanceof ProviderPart && null != provider && provider.canRender(((ProviderPart) part).field)) { sb.append(((ProviderPart) part).render(provider)); } else { sb.append(part.raw); } } return sb.toString(); } private List<TokenizingPart> compilePattern() { List<TokenizingPart> compiledList = new ArrayList<>(); int startIndex = 0; int endIndex = 0; while (-1 != startIndex && -1 != endIndex && endIndex < pattern.length()) { // find 'start of token' startIndex = pattern.indexOf("${", endIndex); // save the 'not-token' part if (-1 != startIndex) { if (0 < startIndex) { compiledList.add(new StringPart(pattern.substring(endIndex, startIndex))); } startIndex += 2; // find 'end of token' endIndex = pattern.indexOf("}", startIndex); // replace the token String raw = pattern.substring(startIndex - 2, endIndex + 1); String token = pattern.substring(startIndex, endIndex); // get the parts String[] tokenParts = token.split(delimiter); String formatter = null; if (3 == tokenParts.length) { formatter = tokenParts[2]; } if (tokenParts[0].equalsIgnoreCase("header")) { compiledList.add(pickHeaderType(raw, tokenParts[1], formatter)); } else if (token.startsWith("provider")) { compiledList.add(new ProviderPart(raw, tokenParts[1], formatter)); } else { throw new ChronicleException("unknown qualifier on token, " + token); } endIndex++; } else { compiledList.add(new StringPart(pattern.substring(endIndex))); } } return compiledList; } private TokenizingPart pickHeaderType(String raw, String header, String formatter) { if ("date".equals(formatter)) { return new HeaderDatePart(raw, header); } else { return new HeaderStringPart(raw, header); } } public int hashCode() { return HashCodeBuilder.reflectionHashCode(this, false); } public boolean equals(Object o) { return EqualsBuilder.reflectionEquals(this, o, false); } public String toString() { return ToStringBuilder.reflectionToString(this); } public List<TokenizingPart> getCompiledPattern() { return compiledPattern; } // ---------- abstract class TokenizingPart { final String raw; TokenizingPart(String raw) { this.raw = raw; } public int hashCode() { return HashCodeBuilder.reflectionHashCode(this, false); } public boolean equals(Object o) { return EqualsBuilder.reflectionEquals(this, o, false); } public String toString() { return ToStringBuilder.reflectionToString(this); } } class StringPart extends TokenizingPart { StringPart(String raw) { super(raw); } public int hashCode() { return HashCodeBuilder.reflectionHashCode(this, false); } public boolean equals(Object o) { return EqualsBuilder.reflectionEquals(this, o, false); } public String toString() { return ToStringBuilder.reflectionToString(this); } } abstract class HeaderPart extends TokenizingPart { final String header; HeaderPart(String raw, String header) { super(raw); this.header = header; } public abstract String render(Event event); public int hashCode() { return HashCodeBuilder.reflectionHashCode(this, false); } public boolean equals(Object o) { return EqualsBuilder.reflectionEquals(this, o, false); } public String toString() { return ToStringBuilder.reflectionToString(this); } } class HeaderStringPart extends HeaderPart { HeaderStringPart(String raw, String header) { super(raw, header); } @Override public String render(Event event) { return event.getHeaders().get(header); } public int hashCode() { return HashCodeBuilder.reflectionHashCode(this, false); } public boolean equals(Object o) { return EqualsBuilder.reflectionEquals(this, o, false); } public String toString() { return ToStringBuilder.reflectionToString(this); } } class HeaderDatePart extends HeaderPart { private final DateTimeFormatter fmt = DateTimeFormat.forPattern("yyyy-MM-dd").withZone(DateTimeZone.UTC); HeaderDatePart(String raw, String header) { super(raw, header); } @Override public String render(Event event) { return fmt.print(Long.parseLong(event.getHeaders().get(header))); } public int hashCode() { return HashCodeBuilder.reflectionHashCode(this, false); } public boolean equals(Object o) { return EqualsBuilder.reflectionEquals(this, o, false); } public String toString() { return ToStringBuilder.reflectionToString(this); } } class ProviderPart extends TokenizingPart { final String field; final String formatter; ProviderPart(String raw, String field, String formatter) { super(raw); this.field = field; this.formatter = formatter; } public String render(TokenValueProvider provider) { return provider.render(field); } public int hashCode() { return HashCodeBuilder.reflectionHashCode(this, false); } public boolean equals(Object o) { return EqualsBuilder.reflectionEquals(this, o, false); } public String toString() { return ToStringBuilder.reflectionToString(this); } } }