StepContext

StepContext源代码详解

从StepContext的源代码看，StepContext的构造方法中有StepExecution。

package org.springframework.batch.core.scope.context;

import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Properties;
import java.util.Set;
import org.springframework.batch.core.JobParameter;
import org.springframework.batch.core.StepExecution;
import org.springframework.batch.core.UnexpectedJobExecutionException;
import org.springframework.batch.repeat.context.SynchronizedAttributeAccessor;
import org.springframework.util.Assert;

public class StepContext extends SynchronizedAttributeAccessor {
    private StepExecution stepExecution;
    private Map<String, Set<Runnable>> callbacks = new HashMap();

    public StepContext(StepExecution stepExecution) {
        Assert.notNull(stepExecution, "A StepContext must have a non-null StepExecution");
        this.stepExecution = stepExecution;
    }

    public String getStepName() {
        return this.stepExecution.getStepName();
    }

    public String getJobName() {
        Assert.state(this.stepExecution.getJobExecution() != null, "StepExecution does not have a JobExecution");
        Assert.state(this.stepExecution.getJobExecution().getJobInstance() != null, "StepExecution does not have a JobInstance");
        return this.stepExecution.getJobExecution().getJobInstance().getJobName();
    }

    public Properties getSystemProperties() {
        return System.getProperties();
    }

    public Map<String, Object> getStepExecutionContext() {
        Map<String, Object> result = new HashMap();
        Iterator i$ = this.stepExecution.getExecutionContext().entrySet().iterator();

        while(i$.hasNext()) {
            Map.Entry<String, Object> entry = (Map.Entry)i$.next();
            result.put(entry.getKey(), entry.getValue());
        }

        return Collections.unmodifiableMap(result);
    }

    public Map<String, Object> getJobExecutionContext() {
        Map<String, Object> result = new HashMap();
        Iterator i$ = this.stepExecution.getJobExecution().getExecutionContext().entrySet().iterator();

        while(i$.hasNext()) {
            Map.Entry<String, Object> entry = (Map.Entry)i$.next();
            result.put(entry.getKey(), entry.getValue());
        }

        return Collections.unmodifiableMap(result);
    }

    public Map<String, Object> getJobParameters() {
        Map<String, Object> result = new HashMap();
        Iterator i$ = this.stepExecution.getJobParameters().getParameters().entrySet().iterator();

        while(i$.hasNext()) {
            Map.Entry<String, JobParameter> entry = (Map.Entry)i$.next();
            result.put(entry.getKey(), ((JobParameter)entry.getValue()).getValue());
        }

        return Collections.unmodifiableMap(result);
    }

    public void registerDestructionCallback(String name, Runnable callback) {
        synchronized(this.callbacks) {
            Set<Runnable> set = (Set)this.callbacks.get(name);
            if (set == null) {
                set = new HashSet();
                this.callbacks.put(name, set);
            }

            ((Set)set).add(callback);
        }
    }

    private void unregisterDestructionCallbacks(String name) {
        synchronized(this.callbacks) {
            this.callbacks.remove(name);
        }
    }

    public Object removeAttribute(String name) {
        this.unregisterDestructionCallbacks(name);
        return super.removeAttribute(name);
    }

    public void close() {
        List<Exception> errors = new ArrayList();
        Map<String, Set<Runnable>> copy = Collections.unmodifiableMap(this.callbacks);
        Iterator i$ = copy.entrySet().iterator();

        while(i$.hasNext()) {
            Map.Entry<String, Set<Runnable>> entry = (Map.Entry)i$.next();
            Set<Runnable> set = (Set)entry.getValue();
            Iterator i$ = set.iterator();

            while(i$.hasNext()) {
                Runnable callback = (Runnable)i$.next();
                if (callback != null) {
                    try {
                        callback.run();
                    } catch (RuntimeException var9) {
                        errors.add(var9);
                    }
                }
            }
        }

        if (!errors.isEmpty()) {
            Exception error = (Exception)errors.get(0);
            if (error instanceof RuntimeException) {
                throw (RuntimeException)error;
            } else {
                throw new UnexpectedJobExecutionException("Could not close step context, rethrowing first of " + errors.size() + " exceptions.", error);
            }
        }
    }

    public StepExecution getStepExecution() {
        return this.stepExecution;
    }

    public String getId() {
        Assert.state(this.stepExecution.getId() != null, "StepExecution has no id.  It must be saved before it can be used in step scope.");
        return "execution#" + this.stepExecution.getId();
    }

    public boolean equals(Object other) {
        if (!(other instanceof StepContext)) {
            return false;
        } else if (other == this) {
            return true;
        } else {
            StepContext context = (StepContext)other;
            return context.stepExecution == this.stepExecution ? true : this.stepExecution.equals(context.stepExecution);
        }
    }

    public int hashCode() {
        return this.stepExecution.hashCode();
    }

    public String toString() {
        return super.toString() + ", stepExecutionContext=" + this.getStepExecutionContext() + ", jobExecutionContext=" + this.getJobExecutionContext() + ", jobParameters=" + this.getJobParameters();
    }
}