要执行这些 Java 程序你需要为每个listing创建一个独立的.java文件然后分别编译和运行。以下是每个程序的核心要点、执行步骤和预期输出。1. 创建并编译 Java 文件为每个listing创建一个对应的.java文件。文件名必须与文件中定义的public class名称完全一致。文件名对应的 Listing包含的类MakeString.javaListing 1MakeStringSubStringCons.javaListing 2SubStringConsConCat.javaListing 3ConCattoStringDemo.javaListing 4Box,toStringDemogetCharsDemo.javaListing 5getCharsDemoequalsDemo.javaListing 6equalsDemoEqualsNotEqualTo.javaListing 7EqualsNotEqualToSortString.javaListing 8SortStringindexOfDemo.javaListing 9indexOfDemoStringReplace.javaListing 10StringReplaceUseTrim.javaListing 11UseTrimChangeCase.javaListing 12ChangeCaseStringJoinDemo.javaListing 13StringJoinDemoStringBufferDemo.javaListing 14StringBufferDemosetCharAtDemo.javaListing 15setCharAtDemoappendDemo.javaListing 16appendDemoinsertDemo.javaListing 17insertDemoReverseDemo.javaListing 18ReverseDemodeleteDemo.javaListing 19deleteDemoreplaceDemo.javaListing 20replaceDemoIndexOfDemo.javaListing 21IndexOfDemo使用javac命令编译所有文件javac *.java2. 运行程序及预期输出使用java命令运行每个程序的主类。Listing 1:MakeStringjava MakeString输出Java Java说明演示了从字符数组和现有字符串构造新String对象 。Listing 2:SubStringConsjava SubStringCons输出ABCDEF CDE说明演示了从字节数组及其子集构造字符串。Listing 3:ConCatjava ConCat输出This could have been a very long line that would have wrapped around. But string concatenation prevents this.说明演示了使用进行字符串连接以格式化长字符串。Listing 4:toStringDemojava toStringDemo输出Dimensions are 10.0 by 14.0 by 12.0. Box b: Dimensions are 10.0 by 14.0 by 12.0.说明演示了重写toString()方法使得对象在与字符串连接或直接打印时能输出自定义信息 。Listing 5:getCharsDemojava getCharsDemo输出demo说明演示了getChars()方法用于将字符串的一部分复制到字符数组中 。Listing 6:equalsDemojava equalsDemo输出Hello equals Hello - true Hello equals Good-bye - false Hello equals HELLO - false Hello equalsIgnoreCase HELLO - true说明演示了equals()和equalsIgnoreCase()方法用于比较字符串内容 。Listing 7:EqualsNotEqualTojava EqualsNotEqualTo输出Hello equals Hello - true Hello Hello - false说明关键演示了比较对象引用地址而equals()比较内容。s2是new出来的新对象引用不同 。Listing 8:SortStringjava SortString输出Now aid all come country for good is men of the the their time to to说明使用compareTo()方法进行字符串字典序比较并实现冒泡排序。Listing 9:indexOfDemojava indexOfDemo输出Now is the time for all good men to come to the aid of their country. indexOf(t) 7 lastIndexOf(t) 65 indexOf(the) 7 lastIndexOf(the) 43 indexOf(t, 10) 11 lastIndexOf(t, 60) 55 indexOf(the, 10) 43 lastIndexOf(the, 60) 43说明演示了indexOf()和lastIndexOf()方法查找字符或子串的位置 。Listing 10:StringReplacejava StringReplace输出This is a test. This is, too. Thwas is a test. This is, too. Thwas was a test. This is, too. Thwas was a test. Thwas is, too. Thwas was a test. Thwas was, too.说明手动实现了子串替换逻辑循环查找并替换所有is为was。Listing 11:UseTrimjava UseTrim输出示例交互式Enter stop to quit. Enter State: Illinois (用户输入带空格) Capital is Springfield. California Capital is Sacramento. stop说明演示了trim()方法去除用户输入首尾空白字符使比较更准确 。Listing 12:ChangeCasejava ChangeCase输出Original: This is a test. Uppercase: THIS IS A TEST. Lowercase: this is a test.说明演示了toUpperCase()和toLowerCase()方法。Listing 13:StringJoinDemojava StringJoinDemo输出Alpha Beta Gamma John, ID#: 569, E-mail: JohnHerbSchildt.com说明演示了String.join()静态方法用指定分隔符连接多个字符串。Listing 14:StringBufferDemojava StringBufferDemo输出buffer Hello length 5 capacity 21**说明**演示了StringBuffer的length()字符数和capacity()当前分配的容量。Listing 15:setCharAtDemojava setCharAtDemo输出buffer before Hello charAt(1) before e buffer after Hi charAt(1) after i说明演示了setCharAt()修改指定索引的字符以及setLength()截断缓冲区。Listing 16:appendDemojava appendDemo输出a 42!说明演示了StringBuffer.append()的链式调用可将各种类型数据追加到缓冲区 。Listing 17:insertDemojava insertDemo输出I like Java!说明演示了insert()方法在指定位置插入字符串。Listing 18:ReverseDemojava ReverseDemo输出abcdef fedcba说明演示了reverse()方法反转缓冲区内容。Listing 19:deleteDemojava deleteDemo输出After delete: This a test. After deleteCharAt: his a test.说明演示了delete(int start, int end)和deleteCharAt(int index)方法。Listing 20:replaceDemojava replaceDemo输出After replace: This was a test.说明演示了replace(int start, int end, String str)方法。Listing 21:IndexOfDemojava IndexOfDemo输出First index: 0Last index: 8说明演示了StringBuffer的indexOf()和lastIndexOf()方法。参考来源java字符串的运用代码_使用javap分析Java的字符串操作java字符串常量的操作Java中如何将字符串转换为JSON格式字符串Java字符串分割的三种方法Java种过滤掉某个字符串