我不久前来到这里试图找出是否有一种方法可以自动对案例语句进行排序。Eclipse 没有自动执行此操作的答案。所以我想找到一种方法来做到这一点。可悲的是，这似乎没有在任何地方解决。这是每个人都需要做的事情吗？可能不会。
【问题讨论】：
标签： java sorting arraylist switch-statement
这是我的解决方案：
主要调用：
package com.debug;
import java.io.IOException;
public class DebugMain {
public static void main(String[] args) {
fixCases();
}
public static void fixCases() {
String filePath = System.getProperty("user.home").replace("\\", "/") + "/Documents/";
String fileName = "case.txt";
System.out.println("Organizing cases: " + filePath + fileName);
CaseHandler ch = new CaseHandler(filePath + fileName, CaseType.Integer);
try {
ch.readFile();
ch.sortCases();
ch.writeCases(filePath + "casetest.txt");
} catch (IOException e) {
e.printStackTrace();
}
System.out.println("Organizing complete.");
}
}
案例处理程序：
package com.debug;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
/**
* This handler allows you to read from a text file a list of case statements, sort the case statements<br />
* in natural order, and write to a file.
*
* @author Vincent
*/
public class CaseHandler {
/**
* This denotes the use of numerical or text based case statements.
*/
public enum CaseType {
String, Integer;
}
private boolean autoSort = false;
private ArrayList<Case> cases = new ArrayList<Case>();
private CaseType caseType;
private File file;
/**
* This construcs a basic <code>CaseHandler</code> in which a file must be provided
* within the {@link #readFile(String)} method.
* <b>Note:</b> The file expected should always be a text file with only the case statements.<br />
* The formatting is not important.
*
* @param caseType The type of case this instance should use.
* @see {@link CaseType}, {@link CaseHandler}
*/
public CaseHandler(CaseType caseType) {
this.caseType = caseType;
}
/**
* This construcs a <code>CaseHandler</code> with a file provided.<br />
* <b>Note:</b> The file expected should always be a text file with only the case statements.<br />
* The formatting is not important.
*
* @param fileName The full file path and name to be read from and/or written to.
* @param caseType The type of case this instance should use.
* @see {@link CaseType}, {@link CaseHandler}
*/
public CaseHandler(String fileName, CaseType caseType) {
this.caseType = caseType;
this.file = new File(fileName);
}
/**
* This construcs a <code>CaseHandler</code> with a file provided.<br />
* <b>Note:</b> The file expected should always be a text file with only the case statements.<br />
* The formatting is not important.
*
* @param fileName The full file path and name to be read from and/or written to.
* @param caseType The type of case this instance should use.
* @param autoSort Enables auto sorting in the {@link #readFile()}
*/
public CaseHandler(String fileName, CaseType caseType, boolean autoSort) {
this.caseType = caseType;
this.file = new File(fileName);
this.autoSort = autoSort;
}
/**
* Reads the file where the case statements are stored line by line.<br />
* When the word case is found it creates a new temp <code>ArrayList</code> of <code>String</code>. <br />
* If a temp <code>ArrayList</code> already exists then it overwrites the <code>ArrayList</code>. <br />
* When the word break is found it then creates a <code>Case<code> object and stores the lines.<br />
* This then stores the <code>Case</code> objects into an <code>ArrayList</code> for later use.
* If auto sort has been enabled in the constructor then this will also sort the <code>Case</code> objects.
*
* @throws IOException
* @see {@link ArrayList}, {@link FileReader}, {@link BufferedReader}, {@link Case}
*/
public void readFile() throws IOException {
if (this.file != null && this.file.exists()) {
FileReader fr = null;
BufferedReader br = null;
try {
fr = new FileReader(this.file);
br = new BufferedReader(fr);
String line = "";
ArrayList<String> lines = null;
while ((line = br.readLine()) != null) {
if (line.contains("case")) {
if (lines != null && lines.get(lines.size() - 1).contains("break")) {
lines = new ArrayList<String>();
} else {
lines = new ArrayList<String>();
}
}
lines.add(line);
if (line.contains("break")) {
String caseName = lines.get(0).replace("case", "").replace(":", "").trim();
Case aCase = null;
if (caseType == CaseType.Integer) {
aCase = new Case(Integer.parseInt(caseName), lines);
} else if (caseType == CaseType.String) {
aCase = new Case(caseName, lines);
}
cases.add(aCase);
}
}
if (this.autoSort) {
this.sortCases();
}
} finally {
if (br != null) {
br.close();
}
if (fr != null) {
fr.close();
}
}
} else {
System.out.println("File " + this.file.getName() + " does not exist!");
}
}
/**
* Reads the file where the case statements are stored line by line.<br />
* When the word case is found it creates a new temp <code>ArrayList</code> of <code>String</code>. <br />
* If a temp <code>ArrayList</code> already exists then it overwrites the <code>ArrayList</code>. <br />
* When the word break is found it then creates a <code>Case<code> object and stores the lines.<br />
* This then stores the <code>Case</code> objects into an <code>ArrayList</code> for later use.
* If auto sort has been enabled in the constructor then this will also sort the <code>Case</code> objects.
*
* @param fileName The full file path and name to be read from and/or written to.
* @throws IOException
* @see {@link ArrayList}, {@link FileReader}, {@link BufferedReader}, {@link Case}
*/
public void readFile(String fileName) throws IOException {
this.file = new File(fileName);
if (this.file != null && this.file.exists()) {
FileReader fr = null;
BufferedReader br = null;
try {
fr = new FileReader(this.file);
br = new BufferedReader(fr);
String line = "";
ArrayList<String> lines = null;
while ((line = br.readLine()) != null) {
if (line.contains("case")) {
if (lines != null && lines.get(lines.size() - 1).contains("break")) {
lines = new ArrayList<String>();
} else {
lines = new ArrayList<String>();
}
}
lines.add(line);
if (line.contains("break")) {
String caseName = lines.get(0).replace("case", "").replace(":", "").trim();
Case aCase = null;
if (caseType == CaseType.Integer) {
aCase = new Case(Integer.parseInt(caseName), lines);
} else if (caseType == CaseType.String) {
aCase = new Case(caseName, lines);
}
cases.add(aCase);
}
}
if (this.autoSort) {
this.sortCases();
}
} finally {
if (br != null) {
br.close();
}
if (fr != null) {
fr.close();
}
}
} else {
System.out.println("File " + this.file.getName() + " does not exist!");
}
}
/**
* Sorts the {@link ArrayList} in alphabetical or numerical order.<br />
* <b>Note:</b> This will <b>NOT</b> sort clusters of case statements.
* @see {@link Collections#sort(java.util.List)}
*/
public void sortCases() {
if (cases.size() > 0) {
Collections.sort(cases, Comparator.naturalOrder());
}
}
/**
* Overwrites the file provided to the <code>CaseHandler</code> with the cases list.
*
* @throws IOException
* @see {@link ArrayList}, {@link FileWriter}, {@link BufferedWriter}, {@link Case}
*/
public void writeCases() throws IOException {
if (this.file.exists()) {
FileWriter fw = null;
BufferedWriter bw = null;
try {
fw = new FileWriter(this.file);
bw = new BufferedWriter(fw);
for (Case aCase : cases) {
for (String line : aCase.getLines()) {
bw.write(line);
bw.newLine();
}
}
} finally {
if (bw != null) {
bw.close();
}
if (fw != null) {
fw.close();
}
}
}
}
/**
* Overwrites the file provided to with the cases list.
*
* @param fileName The full file path and name to be read from and/or written to.
* @throws IOException
* @see {@link ArrayList}, {@link FileWriter}, {@link BufferedWriter}, {@link Case}
*/
public void writeCases(String fileName) throws IOException {
File outFile = new File(fileName);
if (!outFile.exists()) {
outFile.createNewFile();
}
if (outFile.exists()) {
FileWriter fw = null;
BufferedWriter bw = null;
try {
fw = new FileWriter(outFile);
bw = new BufferedWriter(fw);
for (Case aCase : cases) {
for (String line : aCase.getLines()) {
bw.write(line);
bw.newLine();
}
}
} finally {
if (bw != null) {
bw.close();
}
if (fw != null) {
fw.close();
}
}
}
}
/**
* Changes the case type.
*
* @param caseType The new type of case this instance should use.
* @see {@link CaseType}
*/
public void setCaseType(CaseType caseType) {
this.caseType = caseType;
}
}
案例：
package com.debug;
import java.util.ArrayList;
/**
* This is the individual case statement starting at <code>case (Integer or String):</code> <br />
* The last line stored in the instance will be the <code>break;</code> statement.
*
* @author Vincent
*
*/
public class Case implements Comparable<Case> {
private int nameInt;
private String nameStr = null;
private ArrayList<String> lines;
/**
* Constructs a new <code>Case</code> using integer values as the name.
*
* @param nameInt The integer value name
* @param lines The lines within this case statement
* @see {@link ArrayList}
*/
public Case(int nameInt, ArrayList<String> lines) {
this.nameInt = nameInt;
this.lines = lines;
}
/**
* Constructs a new <code>Case</code> using string values as the name.
*
* @param nameStr The string value name
* @param lines The lines within this case statement
* @see {@link ArrayList}
*/
public Case(String nameStr, ArrayList<String> lines) {
this.nameStr = nameStr;
this.lines = lines;
}
@Override
public int compareTo(Case aCase) {
if (this.nameStr != null) {
return this.nameStr.compareTo(aCase.getNameStr());
} else {
if (this.nameInt < aCase.getNameInt()) {
return -1;
} else if (this.nameInt > aCase.getNameInt()) {
return 1;
} else {
return 0;
}
}
}
/**
* Returns the lines stored in this <code>Case</code> instance.
*
* @return {@link ArrayList}
*/
public ArrayList<String> getLines() {
return this.lines;
}
/**
* Returns the integer name of this <code>Case</code> instance.
*
* @return {@link Integer}
*/
public int getNameInt() {
return this.nameInt;
}
/**
* Returns the string name of this <code>Case</code> instance.
*
* @return {@link String}
*/
public String getNameStr() {
return this.nameStr;
}
}
示例输入：
case 338:
// Code
break;
case 852:
// Code
break;
case 2:
// Code
break;
case 696:
// Code
break;
示例输出：
case 2:
// Code
break;
case 338:
// Code
break;
case 696:
// Code
break;
case 852:
// Code
break;
希望这可能会帮助某人。我需要这个，因为我正在查看一长串案例（准确地说是 1000 个），这些案例没有按特定顺序排序或有任何理由按这种方式排序。所以我想以自然的顺序看到它们。
【讨论】：