Question

即使我在Youtube上关注某人并复制他的代码，我仍然会收到此错误。他没有得到错误，但我做到了。

以下代码位于课程[ERROR] Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.3:compile (default-compile) on project benchmark: Compilation failure -> [Help 1] org.apache.maven.lifecycle.LifecycleExecutionException: Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.3:compile (default-compile) on project benchmark: Compilation failure at org.apache.maven.lifecycle.internal.MojoExecutor.execute (MojoExecutor.java:213) at org.apache.maven.lifecycle.internal.MojoExecutor.execute (MojoExecutor.java:154) at org.apache.maven.lifecycle.internal.MojoExecutor.execute (MojoExecutor.java:146) at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject (LifecycleModuleBuilder.java:117) at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject (LifecycleModuleBuilder.java:81) at org.apache.maven.lifecycle.internal.builder.singlethreaded.SingleThreadedBuilder.build (SingleThreadedBuilder.java:51) at org.apache.maven.lifecycle.internal.LifecycleStarter.execute (LifecycleStarter.java:128) at org.apache.maven.DefaultMaven.doExecute (DefaultMaven.java:309) at org.apache.maven.DefaultMaven.doExecute (DefaultMaven.java:194) at org.apache.maven.DefaultMaven.execute (DefaultMaven.java:107) at org.apache.maven.cli.MavenCli.execute (MavenCli.java:955) at org.apache.maven.cli.MavenCli.doMain (MavenCli.java:290) at org.apache.maven.cli.MavenCli.main (MavenCli.java:194) at sun.reflect.NativeMethodAccessorImpl.invoke0 (Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke (Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke (Unknown Source) at java.lang.reflect.Method.invoke (Unknown Source) at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced (Launcher.java:289) at org.codehaus.plexus.classworlds.launcher.Launcher.launch (Launcher.java:229) at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode (Launcher.java:415) at org.codehaus.plexus.classworlds.launcher.Launcher.main (Launcher.java:356) Caused by: org.apache.maven.plugin.compiler.CompilationFailureException: Compilation failure at org.apache.maven.plugin.compiler.AbstractCompilerMojo.execute (AbstractCompilerMojo.java:915) at org.apache.maven.plugin.compiler.CompilerMojo.execute (CompilerMojo.java:129) at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo (DefaultBuildPluginManager.java:134) at org.apache.maven.lifecycle.internal.MojoExecutor.execute (MojoExecutor.java:208) at org.apache.maven.lifecycle.internal.MojoExecutor.execute (MojoExecutor.java:154) at org.apache.maven.lifecycle.internal.MojoExecutor.execute (MojoExecutor.java:146) at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject (LifecycleModuleBuilder.java:117) at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject (LifecycleModuleBuilder.java:81) at org.apache.maven.lifecycle.internal.builder.singlethreaded.SingleThreadedBuilder.build (SingleThreadedBuilder.java:51) at org.apache.maven.lifecycle.internal.LifecycleStarter.execute (LifecycleStarter.java:128) at org.apache.maven.DefaultMaven.doExecute (DefaultMaven.java:309) at org.apache.maven.DefaultMaven.doExecute (DefaultMaven.java:194) at org.apache.maven.DefaultMaven.execute (DefaultMaven.java:107) at org.apache.maven.cli.MavenCli.execute (MavenCli.java:955) at org.apache.maven.cli.MavenCli.doMain (MavenCli.java:290) at org.apache.maven.cli.MavenCli.main (MavenCli.java:194) at sun.reflect.NativeMethodAccessorImpl.invoke0 (Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke (Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke (Unknown Source) at java.lang.reflect.Method.invoke (Unknown Source) at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced (Launcher.java:289) at org.codehaus.plexus.classworlds.launcher.Launcher.launch (Launcher.java:229) at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode (Launcher.java:415) at org.codehaus.plexus.classworlds.launcher.Launcher.main (Launcher.java:356) [ERROR] [ERROR] [ERROR] For more information about the errors and possible solutions, please read the following articles: [ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/MojoFailureException

中

Cart

以下代码位于课程// Calculating the total price int total = 0 ; for(Order order:cart) total += (Integer.parseInt(order.getPrice())) * (Integer.parseInt(order.getQuantity())); Locale locale = new Locale("en" , "US" ); NumberFormat fmt = NumberFormat.getCurrencyInstance(locale); txtTotalPrice.setText(fmt.format(total));

中

CartAdapter

Answer 1

我order.getPrice()可能是null。order.getQuantity()可能是null

如果其中一个或两个都为空，则会导致NumberFormatException

所以你可以这样做。

如果你想使用它们。

total += (Integer.parseInt(TextUtils.isEmpty(order.getPrice()) ? "0" : order.getPrice())) * (Integer.parseInt(TextUtils.isEmpty(order.getQuantity()) ? "0" : order.getQuantity()));

并且

int price = (Integer.parseInt(TextUtils.isEmpty(listData.get(position).getPrice()) ? "0" : listData.get(position).getPrice()))
            *(TextUtils.isEmpty(listData.get(position).getQuantity()) ? "0" : listData.get(position).getQuantity());

注意

你可以这样做，如果你的回答为空，你可以返回一个默认值。它不会导致NumberFormatException。

TextUtils.isEmpty(response) ? "0" : response;

java.lang.NumberFormatException：对于输入字符串：＆＃34; null＆＃34; ..无法弄清楚原因

1 个答案: